WW2 Tank-Anti Tank Gun Muzzle Energies

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WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2016-12-17 06:46pm

Wrote this this morning while it was too icy to go outside. Making it it's own thread so I can update it later

***
Introduction: Penetration tables mattered on the battlefield but are very difficult to compare due to differing test standards, actual targets employing treachery like 3D angles and trees and the fact that ammuntion and gun performance varied in actual service conditions. This is why many penetration tables, including all German tables, are V50 values. That was a reasonable basis to open fire upon. But doesn't tell you what the worst case performance would be either (standards for how wide a spread was allowed varied, in modern day its pretty tight)

When it came to the gross impact on vehicle design, logistics and economic impact though simply examining relevant muzzle energies tells us most of what we want to know. How much energy the gun had to output largely defined how big and awkward it was going to be and how much metal would get absorbed making it. How big a vehicle was going to come into play moving or carrying it. This little report aims simply to make that comparison.

All powers generally believed they had good quality ammunition when making decisions, though as I've seen the by far least experienced of the factions in the form of the US made some significantly poor decisions and mistakes with its ammo design of the 3in gun. A lot of that was tied to the sudden decision to Americanize the 6pdr as 57mm (it just could not be US produced without doing this) when the Ordnance Corps was already over tasked. Germany in contrast having begun total war mobilization years ahead of any other relevant power, had the luxury of already having combat tested its 88mm rounds and other munitions as early as 1938 in Spain.

The numbers following have been calculated using whatever the pieces normal service round was or primarily was, in all cases some kind of full caliber steel AP shot or shell. APCR type and various hyper velocity rounds generally did not increase muzzle energy or barely so, they were vital for increasing the impact velocity range but this advantage would naturally decline with distance at an accelerated rate. Such ammo was also incredibly sensitive to detail design, all of which was poor by modern standards. As such the main comparison should be with the primary service ammunition, this is what was defining everyone's actual gun and carriage/mount characteristics.

The notes are simply what came to mind when collecting the information

Tank/Anti Tank Gun Muzzle Energy Plots:
Naziwaffen

3.7cm Pak 36 .685kg at 745m/s = 190,615 joules
5cm Pak 38 2.06kg at 830m/s = 720,496 joules
7.5cm StuK 40 6.8kg at 740m/s = 1,867,538 joules
7.5cm KwK 40 6.8kg at 790m/s = 2,128,345 joules
7.5cm KwK 42 6.8kg at 925m/s = 2,918,028 joules

8.8cm KwK 36 10.4kg at 773m/s = 3,115,982 joules
8.8cm KwK 43 10.4kg at 1000m/s = 5,215,656 joules
12.8cm Kwk 44 28.3kg at 950m/s = 12,809,234 joules

-Note 1) The KwK 40 is Pak 40. The StuK gun would still perform better with a new barrel then a Pak 40 with a worn one.
-Note 2) Germany never fielded a towed version of the KwK 42, some Russian and American projects were similar to what that would have looked like. Since such guns end up requiring very large prime movers either way reality would tend to favor bringing the bigger gun.
-Note 3) 1000m/sand 3000fps was sometimes seem as a special design point in this time frame, but hydrodynamic theory was still too primitive to exploit it in any very useful sense. All WW2 anti tank ammunition design more or less sucked in hindsight. APRC only worked within a narrow range of obliquity and past that even 2in thick steel plates not only could but always would deflect major caliber hits. This means a Sherman could and did bounce Tiger hits off its glacis.

That led into eventually the NATO triple heavy spaced armor array which negated everything from WW2 tank calibers. Its two spaced plates would just always knock the round to high obliquity, at which point the 80mm backing plate can stop anything short of a superheavy artillery round if it hits sideways!

-Note 4) About 800m/s was the velocity limit for WW2 guns with long barrel lives, artillery type weapons did not want to exceed this. Naturally some of the best anti tank weapons around were the ones firing at much higher velocity ranges. However high erosion rates in high velocity guns, particularly with WW2 gunmaking also meant a rapid and steady loss of actual firing velocity and accuracy. 10% loss of velocity was usually the life of a gun. That could be a very serious erosion of performance for a tank gun, for artillery the main concern was it made accuracy worse and worse.

Plots:
Western Allied Victory Cannon

2pdr QF 1.08kg at 792 m/s= 339,860 joules
2pdr QF 1.08kg at 853 m/s = 394,178 joules (APHV-T ammo, became standard )
6pdr QF Mk2 2.86kg at 853 m/s = 1,043,842 joules
6pdr QF Mk 4 2.86kg at 892m/s = 1,141,496 joules
75mm M3 6.32kg at 619m/s = 1,206,150 joules
3-inch Gun M5 7kg at 792 m/s =2,202,793 joules
77mm HV 7.71kg at 785m/s = 2,383,866 joules
17pdr QF 7.71kg at 884m/s = 3,021,246 joules
90mm M3 10.914kg at 853m/s = 3,983,662 joules
32pdr QF 14.515kg at 878m/s = 5,608,738 joules

-Not 5) Notice the 2pdr fired a 2lb 6oz round, enough to matter a little in this sort of comparison! It was much more powerful then typical 37mm AT guns. It's margin of future proofing would have mattered had not tank armor escalated not in infinite small steps but sudden leaps to meet tactical needs.
-Note 6) Downgrading the 17pdr chamber to 77mm HV cost a lot of energy performance, but this shows exactly why the 17pdr was so hard to get in a Sherman but the 76mm M5 was not.
-Note 7) One can see why the American 90mm with its standard ammo still had trouble with the heavy glacis plates and gun mantlets of the Panther and King Tiger, it's not really that heavy of a weapon compared to what the Germans were imagining themselves as armored against, based on their own weapons. Importantly its velocity was simply a tad low by the date it was introduced, reflecting the fact that like the original Flak 18 it started as anti aircraft weapon first where barrel lifespan had to be something remotely decent.

Now to illustrate the problem of muzzle energy comparisons with guns that are not attempting a highly similar task, see the following for AFV type close support/assault bombardment type weapons.


95mm QF 11kg at 330m/s = 601,053 joules
15cm StuH 43 38kg at 280m/s = 1,495,126 joules
105mm M4 14.97kg at 472m/s = 1,673,354 joules

Not very powerful looking, but when you trying to lob HE around your goals become much more shifty depending on the exact intent. The velocity can be very low and yet even the 95mm fires to 8,000 yards in its 30 degree elevation tank mount.

Low velocity range weapons like these are not really effective against Maginot style fortifications prior to the invent of HESH type ammunition. The blast will not be tamped enough to remove large amounts of concrete or cut rebar without excessive consumption of killmunition.

In contrast the large bursters are very useful against earth and timber type fortifications and all building types except those of heavy stone masonry. The racking effect of ammunition like this against heavy tanks would be low, but they also had a much better chance of accomplishing absolutely anything with WW2 era HEAT rounds. Literally at that point the low velocity helped save from from the bane of poor fuse delay. HEAT in WW2 had a habit of exploding after a short delay, during which the metal liner would already be deformed by the KE of the impact. The end result was a tendency to work more like a bad HESH round and not generate an efficient warhead jet. Against armor plate this is much less effective. HESH was designed for and optimal for attacking concrete and making large breaches in it, not pinholes.

In contrast a more proper medium-long range artillery bombardment weapon like the 155mm M1 howitzer was as follows

155mm M1 43.13kg at 563m/s = 6,876,794 joules

The Russian gun on the KV-2 BTW is somewhat weaker, though it was much lighter on its towed mount.

152mm M-10 40kg at 508m/s = 5,178,385 joules

These weapons fire about 16,000 and 13,000 yards respectively, and contain around 30 MJ worth of explosive work energy liberated at around 7km/s. Which makes it totally logical why even nose fused HE rounds would start to blow tanks apart given an actual direct hit.

***

Questions/comments/corrections welcomed, though keep in mind some shell weights are rounded because seriously, the tolerances on this stuff weren't that tight in the first place, and muzzle velocity assumes a specific propellent temperature upon firing. Probably not that temperature when you do fire! Correction tables existed but a tank crew had little means of employing that data.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2016-12-18 04:36pm

Revised Western Allied Ranking with key French and Experimental US Guns, new Soviet Plot, new Italian plot + All points comparison. Note how muzzle energy really starts to skyrocket if you went past a good 75mm class of gun...weight of the weapon followed.

Western Allied Cannon

-Fr- 25mm Mle1934 -.326kg at 918 m/s = 137,781 joules
-Br- 2pdr QF – 1.08kg at 792 m/s= 339,860 joules
-Br- 2pdr QF – 1.08kg at 853 m/s = 394,178 joules (APHV-T ammo, became standard )
-Fr- 47mm Mle1937 - 1.726kg at 885m/s = 678105 joule
-Br- 6pdr QF Mk2 – 2.86kg at 853 m/s = 1,043,842 joules
-Br- 6pdr QF Mk 4 – 2.86kg at 892m/s = 1,141,496 joules
-US- 75mm M3 – 6.32kg at 619m/s = 1,206,150 joules
-US- 3-inch Gun – M5 7kg at 792 m/s =2,202,793 joules
-Br- 77mm HV – 7.71kg at 785m/s = 2,383,866 joules
-Br- 17pdr QF – 7.71kg at 884m/s = 3,021,246 joules
-US- 90mm M3 – 10.914kg at 853m/s = 3,983,662 joules
-US- 90mm T15E2 – 10.9kg at 975m/s = 5,196,586 joules
-Br- 32pdr QF – 14.515kg at 878m/s = 5,608,738 joules
-US- 105mm T5E1 – 17.7kg at 914m/s = 7,416,335 joules
-US- 120mm T53 – 23kg at 945m/s = 10,303,731 joules (ammo development not finished)


Soviet Guns

5mm M1937 – 1.429kg at 820m/s = 481,726 joules
76mm L-11 – 6.3kg at 612m/s = 1,183,399 joules
76mm F-34 – 6.3kt at 655m/s = 1,355,428 joules
76mm M1939 – 6.3kg at 662m/s = 1,384,597 joules (divisional field gun)
85mm D-5T – 9.2kg at 792m/s = 2,895,100 joules
122mm M30 – 21.8kg at 515m/s =2,900,635joules
100mm D-10 – 15.6kg at 895m/s 6,264,694 joules
107mm ZIS-6 – 18.86kg @ 830m/s = 6,514,785 joules (abandon 1941)
122mm A-19 – 25kg at 800m/s = 8,025,309 joules
130mm S-70 – 33.4kg at 900m/s = 13,568,645 joules
152mm Br-2 – 49kg at 880m/s = 19,026,231 joules

Italian Guns

-It- 47mm 47/32 – 1.44kg at 630m/s = 286,620 joules
-It- 47mm 47/40 – 1.5kg at 820m/s = 505,660 joules
-It- 75mm L18 – 6.4kg at 450m/s = 649,555 joules
-It- 75mm 75/32 – 6.4kg at 624m/s = 1,249,335 joules
-It- 75mm 75/34 – 6.5kg at 700m/s = 1,597,712 joules
-It- 90mm 90/53 – 10.25kg at 840m/s = 3,626,982 joules


All Rankings * = Axis

-Fr- 25mm Mle1934 -.326kg at 918 m/s = 137,781 joules
*-Ger- 3.7cm Pak 36 – .685kg at 745m/s = 190,615 joules
-It- 47mm 47/32 – 1.44kg at 630m/s = 286,620 joules
-Br- 2pdr QF – 1.08kg at 792 m/s= 339,860 joules
-Sov- 45mm M1937 – 1.429kg at 820m/s = 481,726 joules
*-It- 47mm 47/40 – 1.5kg at 820m/s = 505,660 joules
-Br- 95mm QF – 11kg at 330m/s = 601,053 joules
*-It- 75mm L18 – 6.4kg at 450m/s = 649,555 joules
-Fr- 47mm Mle1937 - 1.726kg at 885m/s = 678,105 joule
*-Ger- 5cm Pak 38 – 2.06kg at 830m/s = 720,496 joules

-Br- 6pdr QF Mk2 – 2.86kg at 853 m/s = 1,043,842 joules
-Br- 6pdr QF Mk 4 – 2.86kg at 892m/s = 1,141,496 joules
-Sov- 76mm L-11 – 6.3kg at 612m/s = 1,183,399 joules
-US- 75mm M3 – 6.32kg at 619m/s = 1,206,150 joules
*-It- 75mm 75/32 – 6.4kg at 624m/s = 1,249,335 joules
-Sov- 76mm F-34 – 6.3kt at 655m/s = 1,355,428 joules
-Sov- 76mm M1939 – 6.3kg at 662m/s = 1,384,597 joules
*-Ger- 15cm StuH – 43 38kg at 280m/s = 1,495,126 joules
*-It- 75mm 75/34 – 6.5kg at 700m/s = 1,597,712 joules
-US- 105mm M4 – 14.97kg at 472m/s = 1,673,354 joules
*-Ger- 7.5cm StuK 40 – 6.8kg at 740m/s = 1,867,538 joules

*-Ger- 7.5cm KwK 40 – 6.8kg at 790m/s = 2,128,345 joules
-US- 3-inch Gun M5 – 7kg at 792 m/s =2,202,793 joules
-Br- 77mm HV – 7.71kg at 785m/s = 2,383,866 joules
-Sov- 85mm D-5T – 9.2kg at 792m/s = 2,895,100 joules
-Sov- 122mm M30 – 21.8kg at 515m/s =2,900,635joules
*-Ger- 7.5cm KwK 42 – 6.8kg at 925m/s = 2,918,028 joules

-Br- 17pdr QF – 7.71kg at 884m/s = 3,021,246 joules
*-Ger- 8.8cm KwK 36 – 10.4kg at 773m/s = 3,115,982 joules
*-It- 90mm 90/53 – 10.25kg at 840m/s = 3,626,982 joules
-US- 90mm M3 – 10.914kg at 853m/s = 3,983,662 joules

-Sov- 152mm M-10 – 40kg at 508m/s = 5,178,385 joules
-US- 90mm T15E2 – 10.9kg at 975m/s = 5,196,586 joules
*-Ger- 8.8cm KwK 43 – 10.4kg at 1000m/s = 5,215,656 joules
-Br- 32pdr QF – 14.515kg at 878m/s = 5,608,738 joules
-Sov-100mm D-10 – 15.6kg at 895m/s 6,264,694 joules
-Sov-107mm ZIS-6 – 18.86kg @ 830m/s = 6,514,785 joules
-US- 155mm M1 – 43.13kg at 563m/s = 6,876,794 joules

-US- 105mm T5E1 – 17.7kg at 914m/s = 7,416,335 joules
-Sov- 122mm A-19 – 25kg at 800m/s = 8,025,309 joules
-US- 120mm T53 – 23kg at 945m/s = 10,303,731 joules
*-Ger- 12.8cm Kwk 44 – 28.3kg at 950m/s = 12,809,234 joules
-Sov- 130mm S-70 – 33.4kg at 900m/s = 13,568,645 joules
-Sov- 152mm Br-2 – 49kg at 880m/s = 19,026,231 joules


The Soviets got as far as mounting the Br-2 on the ISU-152BM in 1945 to counter the King Tiger!!! This has 138 times the muzzle energy of the French 25mm that could handle most tanks in Europe in 1939.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Captain Seafort » 2016-12-18 04:43pm

Out of curiosity, where would the 25pdr with A/Tk ammo fall?
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2016-12-18 05:16pm

25 QF – 9kg at 564 m/s with the AP round = 1,434,991 joules
25pdr QF - 11.3kg at 520 m/s with the HE round at charge super = 1,532,144 joules
25pdr QF - 9kg at 610 m/s for the AP round with supercharge = 1,734,633 joules

The AP supercharge appeared early in the desert war and could be applied to existing shells in the field as this is a modular charge gun, but no further improvement was made to the AP round past that point of note nor does a HEAT round ever seem to have been issued.

All and all the 25pdr was an excellent close support weapon, and because it was designed for a long barrel life for WW1 bombardments and hit some kind of sweet spot with its medium velocity rifling it didn't suffer too much from heavy use of supercharges, supercharge ware is linked to how high it actually makes you shoot after all. But the overall armor performance was a little inferior to say, the Russian 76.2mm field piece because the velocity range was so low, and all and all it was just never going to be great at this role given it's high profile.

The British had intended it as a backup line of AT defense, behind a main line, simply because that's where your direct support artillery naturally lives. its use as the primary frontline AT system in the Western Desert was an emergency measure that severely degraded British effectiveness. It meant they had no massed artillery to stop German attacks in the first place. These guns could stop German armor attacks but they'd generally loose a lot more guns then tanks destroyed.

It's not on the list because the point wasn't to review all field artillery, and the 25pdr is neither verygood against armor nor any form of fortification. Whole British doctrine was a massive volume of fire for suppression, thus why they also had 8 gun batteries of the things instead of 4 or 6.

I would include several experimental/blueprintwaffen German weapons including L100 75mm, 150mm L37 and 170mm L something or other, now that I know they are for certain real, and the German 105mm field gun actually, but I did not find reliable information for their ammo yet.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2016-12-18 05:48pm

If the British had really been forced into it..... I did just confirm the 4.5in gun was the original proposal instead of the 32pdr QF, which was an AT variant of the 3.7in AA gun and the reason that weapon in turn is not on the list.

So 4.5in gun, shell weight was to be 55lb but a velocity is not given. The existing naval cloned land AA gun fired at 746m/s for only 6,965,089 joules. Extending the barrel would have been likely though given the work of designing the gun in the first place, at which point a notional 50-55cal 820m/s version could hit 8,410,240 joules without asking too much from the draftsman.

That the smaller 32pdr was built at all in the dire British economy shows how damn concerned they were with inflating tank sizes, the 4.5in was rejected only on the basis that it would just be too damn big to be practical.

Also actual work was done on a barrel liner hypervelocity 5.25/3.7in and a 4.5/3.7 conversions for the 4000fps velocity anti aircraft role to counter bombers at 50,000ft. These would have been ideal as anti tank weapons, far more so then they would have worked as AA pieces (autoloading then became the path to British tch victory) but only HVAP would exploit the velocity performance which is a slight practical problem.

British never bothered to try to use their 4.5in BL field gun as an anti tank piece, probably because they never had SP mounts for them.

But somehow it's always only German paper projects that could have won the war... :roll:
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby MKSheppard » 2016-12-23 08:07pm

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Swindle1984 » 2016-12-24 10:31pm

Just how much of a performance increase did the squeeze-bore guns bring to the field? I know the Brits eventually just left the barrel adapter off and fired the same ammo, getting better than usual performance and not having to stop and detach the adapter when they wanted to fire regular ammo.

And the German gun got better performance, but was eventually abandoned due to complexity and expense.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Simon_Jester » 2016-12-25 04:10am

Part of the issue is that being able to penetrate thicker tank armor is a very specific advantage. When you ask "how much performance increase do you get from a taper bore gun?" that affects the answer. It's very helpful if you are specifically hunting tanks, especially tanks with armor that is likely to overmatch your gun (i.e. vehicle-mounted 2pdrs and easily manhandled AT guns). But it's not helpful at all if you're doing anything else, and most of the things you fire a cannon at won't be tanks.

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby MKSheppard » 2016-12-25 09:58am

Swindle1984 wrote:Just how much of a performance increase did the squeeze-bore guns bring to the field?


Google is your friend

"littlejohn squeeze bore adaptor"

gives me

https://en.wikipedia.org/wiki/Littlejohn_adaptor

which in turn leads to

http://www.quarryhs.co.uk/sgun.htm

2 pdr AP ( 1.077 kg @ 853 m/sec = 392 KJ)
2 pdr APCBC (1.219 kg @ 792 m/sec = 382 KJ) penetrates 53mm @ 450m @ 30 deg from vertical
2 pdr APSV Mk1 (0.454 kg @ 1,280 m/sec = 372 KJ) penetrates 88mm @ 450m @ 30 deg from vertical
2 pdr APSV Mk 2 (0.567 kg @ 1,143 m/sec = 370 KJ)

You can see that it nearly doubles the performance of the gun, but at the cost of the adapter possibly wearing out after just a few shots and becoming useless. Plus you need really specialized ammunition.

The Germans used squeeze bore in the 28mm sPzB 41 (https://en.wikipedia.org/wiki/2.8_cm_sPzB_41) and at 300 meters, it had a penetration of about 45mm @ 60 degrees on a gun weighing about 500 pounds.

By contrast, the 37mm PAK 36 got about the same performance, but weighed between 720 to 1,000~ pounds (depending on travel condition).
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2016-12-26 02:26am

Yeah the rare 4.2 cm Pak 41 is the exact same weight as the Pak 36 traveling, and could more then kill a Tiger at 100m on paper, also around double performance. But you only get that with APCR and Germany was not making it for this gun after 1942. Most of its tungsten after that point went into aircraft ammunition so people like Rudel could be a lot more effective.

Meanwhile you COULD fire a subcaliber steel AP round with a skirt if you bothered to design it, but most weapons did not have this option except as training ammo, and it wouldn't be too effective. Subcaliber HE existed for some but not all the German guns. The British 2pdr never had HE so no problem on that!

The bigger squeezebore guns didn't really make sense because unless the tungsten supply was unlimited they hit a practical problem of having both low accuracy and a low barrel life. The projectiles are light and while not 17pdr APDS bad, accuracy was never good. Since towed anti tank guns are just vulnerable in principle to stand off attacks by mobile tanks, they need to be able to expend large amounts of ammo to exist.

sPzB 41 seems like the only place this idea really made much sense in the AT role to me. Its so light paratroopers could physically lift it over obstructions recovering it from a drop. The bigger 75mm squeezebore could destroy King Tigers on paper but by then it was a 3,000lb gun too. You need a real truck to tow it, at that point such a specialist weapon is dumb. Recoilless rifles basically doomed this idea postwar and took over the tactical role, but Germany couldn't spam those either because they consumed too much propellant.

I believe the US designed 1 squeezebore 3in AT gun postwar for paratroopers (and another that was conventional) but these went nowhere. Taper bore work was mainly focused on AA postwar, where the raw accuracy of the gun was less important then velocity to reduce the time of flight to altitude if the bomber was at 40-50,000ft. British and US considered squeezebore naval AA pieces, but then went to discarding sabot rounds for all their amazing win guns, before abandoning all in face of miss-ile. On land for AA squeeze bore isn't important, because the guns could be as heavy as they wanted. The German 55/88mm conversion necking down was an interesting idea.

Later in the 1960s the US Army went and designed forging fin 30mm ammunition. Literally a cone skirted round was to be fired into a bore with straight cut rifling in it. Ergo allowing sabot like long rod ammo with without the parasitic mass of of a sabot, and without the sabot risk to helicopter turbine engines. This idea actually worked.

Also I thought up a project which I think has not been done, is adding up the actual weight of everyones tanks and AFVs. Somehow I think Germany would look a lot more in its place on counts like that, since the Sherman and T-34 average heavier then so much German stuff.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Zinegata » 2017-01-02 09:24pm

Excellent charts. I've long been a naysayer of the "Steel Panthers" model of gun penetration vs armor comparisons, as it presumes that a high-energy collision between an anti-tank shell and tank armor is a simple integer comparison with a binary result of "tank penetrated & destroyed or tank bounced shell with no consequence". In reality the collision carries enough energy to be comparable to a bunch of cars crashing into each other, and we all know that such collisions don't exactly leave the cars completely intact even if the drivers survive.

Also, I have to note that tank enthusiasts pay relatively little attention to the concept of zones and angles of immunity - something that's looked into much more deeply when it comes to battleships - in favor of simply presuming frontal hits all of the time. In reality getting hit in the front was uncommon - for the simple reason that the majority of the tank's surface area is not the front plate and that ground combat involves far more situations where an unspotted enemy initiates an ambush.

As an example - the German fanboys and bad Hollywood movies keep assuming that the Tiger I had an awesome front plate that was immune to most Allied tank fire. In reality when somebody tried to simulate the Fury engagement the Tiger died to the first Sherman volley because even the 75mm had a chance of going through the front plate at under 500 meters; and the SUPERIOR GERMAN TIGER COMMANDER decided that the best way to engage three charging Shermans was to charge right back at them head-on to make the range vanish at twice the rate it should have.

This is why the actual Tiger manual advocated an ideal engagement range of 600 meters - still very accurate for the 88mm gun but not close enough that the Sherman 75s and the T-34s with 76.2s can reliably penetrate - and to angle the tank 45 degrees along the horizontal towards the enemy. This may seem counter-intuitive given that it exposes the Tiger's side armor to the enemy (and any Panther or Sherman trying to do the same is basically suicide), but with the Tiger's side being nearly as thick as the front it actually just gives the Tiger-driver a lot of 45-degree slope surface area to bounce shells off. That the only work of fiction to ever depict this sort of angling and zone of immunity awareness is Girls Und Panzer (which features high school girls driving tanks as an extra-curricular school activity) points to the rather shallow understanding of Tankery in popular media in general especially in the West.

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-03 01:40am

So the reality is of course any tank could be useful, but by the end of 1941 if you wanted to fight and win a mobile battle most of the tanks that had fought in 1939-1940 let alone been designed before the war were rubbish. So what does it look like if we compare just tanks, the core of any effective armored division, and just one's that had guns that were seriously effective from 1941 onward? In other words, not 37mm or 37mm like weapons. On that basis I draw the line at the German 50mm, and only then because ultimately all of the stubby ones got upgraded to long ones, if the tank wasn't already dead. This was still only barely able to deal with a T-34 or Sherman.

After all if we listen to the German fans, gun caliber and tank mass are everything.....

Table of Production and Weight of German Tank finished with Guns 50mm or larger.

96 x Panzer III (E) some originally had 37mm) x 19.5 tonnes = 1,872 tonnes
435 x Panzer III (F) most origially had 37mm) x 19.5 tonnes = 8,482.5 tonnes
600 x Panzer III (G) few originally had 37mm) 19.5 tonnes = 11,700 tonnes
308 x Panzer III (H) this is the usefully uparmored one in late 1940) x 21.8 tonnes = 6,714.4 tonnes
2616 x Panzer III (J) x 21.8 tonnes = 57,028.8 tonnes
653 x Panzer III (L) x 22.5 tonnes = 14,692.5 tonnes
250 x Panzer III (M )x 22.5 tonnes = 5,625 tonnes
700 x Panzer III (N) x 22.5 tonnes =15,750 tonnes

Total 5,658 sort of medium tanks at 121,865.2 tonnes but with nothing over a long 50mm gun.

211 x Panzer IV (A/B/C) x 18 tonnes = 3,798 tonnes
229 x Panzer IV (D) first for combat) x 20 tonnes = 4,580 tonnes
233 x Panzer IV (E) note this all that got built by April 1941!) x 20 tonnes = 4,660 tonnes
487 x Panzer IV (F) last short 75mm, some converted to F2) x 20 tonnes = 9,740 tonnes
175 x Panzer IV (F2) early G model with 43cal gun) x 23 tonnes = 4,025 tonnes
412 x Panzer IV G) x 23.6 tonnes = 9,723.2 tonnes
3774 x Panzer IV(H) x 25 tonnes = 94,350 tonnes
2970 x Panzer IV(J) x 25 tonnes = 74,250 tonnes

Total 8,491 medium tanks at 274,151.2 tonnes

3,050 x Panther (D) x 43 tonnes = 131,150 tonnes
2,950 x Panther (G) x 45.5 tonnes = 134,225 tonnes
1,355 x Tiger (1) x 56.5 tonnes = 76,557.5 tonnes
489 x Tiger (2) x 68.5 tonnes = 33,496.5 tonnes

Total heavy tanks 7,844 tanks at 375,429 tonnes

Total tank 21,993 at 771,445.4 tonnes, of which only 16,335 vehicles at 649,580.2 tonnes falls into the Panzer IV+ range.

Note that almost all Panzer III tanks before the E series were primarily used for training, as were almost all the early Panzer IV tanks. Large numbers of all nations tanks simply had to be training vehicles. Only small numbers were fielded in each Panzer division even in May 1940 for trials. German combine arms meant that didn't really matter. Just 40 tanks had the 50mm short gun in May 1940 and probably saw no combat. All the 50mm Panzer IIIs evenutally got the L60 gun or died. These tanks did not compete well with the Sherman or T-34, but weren't totally helpless either.


Now lets look at just the two most common allied tanks, the Sherman and T-34


Table of T-34/Sherman Weights and Ability to Exist

35,488 x T-34-76 x 28.5 tonnes = 1,011,408 tonnes
23,213 x T-34-85 x 34.1 tonnes = 791,563.3 tonnes
33,153 x M4 x 30.3 tonnes = 1,004,535.9 tonnes
250 x M4 JUMBO x 38 tonnes = 9,500 tonnes
10,883 x M4 (76) x 32 tonnes = 348,256 tonnes
4,680 x M4 (105) x 31.5 tonnes = 147,420 tonnes

Total 107,667 tanks at 3,312,683.2 tonnes

This is about 4.29 times more allied weight of M4 and T-34 actual tank then German total actual useful tank mass.

But turrets matter and the US bonus turrets are here (M36s are all conversions)

Bonus Allied Medium Turret Stuff

6,258 x M3 Lee x 27 tonnes = 168,966 tonnes
6,406 M10 x 29 tonnes = 185,774 tonnes
2,507 x M18 x 17.7 tonnes = 44,373.9 tonnes

Total 15,172 bonus vehicles at 399,113.9 tonnes

Arguably the M10 should not be here, or in reduced numbers since most lacked power turret drive. But the fact is it was a turret that actually worked, without the crew super exposed like some German conversions that had traverse, while I'm counting every uselessly broken Panther!

Now lets consider the Soviet heavy tanks that actually worked decently

Soviet Heavy Tanks

3,015 x KV-1 x 45 tonnes = 135,675 tonnes
1,232 x KV-1S x 42.5 tonnes =52,360 tonnes
130 x KV-85 x 46 tonnes = 5,980 tonnes
3854 x IS-2 x 46 tonnes = 177,284 tonnes

Totals 8,231 tanks at 371,299 tonnes

Oh look it's about the same as all the Panthers and Tigers! Though covering a longer production timescale.

Next...

British tanks that had enough gun or armor to matter in mobile warfare mid-late war

British Tanks

144 x Crusader III x 19.7 tonnes = 2,836.8 tonnes
500 x Cavalier x 27 tonnes = 13,500 tonnes
950 x Centuar x 27.6 tonnes = 26,220 tonnes
4,016 Cromwell x 27.6 tonnes = 110,841.6 tonnes
200 x Challenger x 32 tonnes = 6,400 tonnes
1,186 x Comet x 32.7 tonnes = 38,782.2 tonnes
4,338 x Churchill (III+) x 40 tonnes = 173,520 tonnes

Tota 11,334 tanks and 372,100.6 tonnes

The British Valentines did mount some useful 6pdr and up guns, but was functionally a light tank and so not counted here. The Avenger only saw service postwar, Centurion irrelevant number.

Finally, CANADA threw in this

2,000 x Ram x 29 tonnes = 58,000 tonnes

***

Complied Allied Data

T-34/Sherman Total Repeated

-107,667 tanks at 3,312,683.2 tonnes

Additional Medium Tanks/turreted TD

-24,168 vehicles at 627,879.6 tonnes

Allied Heavy Tanks including Churchill but not Jumbo M4

-12,569 tanks at 544,819 tonnes

Final Allied Total 144,404 vehicles at 4,485,381.8 tons.

Lets recall our German Total

Germany major tanks 21,993 at 771,445.4 tonnes, of which only 16,335 vehicles at 649,580.2 tonnes falls into the Panzer IV+ range.

So the allies produced a mere 6.566 times more serious tanks then Germany did, or to point it another way Germany could put one tank directly against every allied tank until the Allies still had 122,471 other medium-heavy tanks left! The battle weight advantage is 5.81 to 1 in Allied favor.

Which shows how sure the Germans had some advantage in heavier tanks later in the war, but obviously not very much of one to produce such a narrow spread of data. Meanwhile the Panzer III was still being fielded in Normandy.


***


Now the inevitable....but Supercasematecladspanzerwaffenwerethevictory! Is sure to be employed by the lame and nazi contaminated, even though the entire point of this comparison is that German Doctrine in favor of mobile warfare was correct, and the only way for Germany to win relevant victories! That means the '100% Stug' strategy so often promulgated as the solution to Germany AFV production is simply not sound.

Appealing to the Germans numerous assault guns means nothing anyway, because then when you throw in all the allied light tanks and self propelled artillery it just slants things even further, and while an M3 was not great for an attack, neither were most of the German vehicles. Germany was never going to win the war standing on the defensive tactically. Such a plan had already failed completely in WW1.

Still so the information is present, I consider the German anti tank and assault gun families, but not conversions of existing tank, or pure artillery vehicles.

1,516 Marders (new builds) at 10.8 tonnes = 16,372.8 tonnes
2,827 Hetzer at 15.75 tonnes = 44,525.25 tonnes
24 x Stug 33B at 21 tonnes =504 tonnes
1,108 x Stug IV at 23 tonnes = 25,484 tonnes
11,385 x Stug III at 24 tonnes = 273,240 tonnes
473 x Nashorn at 24 tonnes = 11,352 tonnes
2,000 x Jagdpanzer IV at 25.8 tonnes = 51,600 tonnes
306 x Brummbar at 28.2 tonnes = 8,629.2 tonnes
415 x Jagdpanther at 45.5 tonnes = 18,882.5 tonnes
91 x Ferdinand at 65 tonnes = 5,915 tonnes
88 x Jagdtiger at 71.7 tonnes = 6,309.6 tonnes
19 x Strumtiger at 68 tonnes = 1,292 tonnes

20,252 various new build anti tank vehicles at 428,106.35 tons

Oh look that only leaves 100,000 allied medium-heavy tanks not countered! And under 1,000 of these German vehicles are actually as heavier then a Sherman tank! In fact the average weight here is only 21.14 tonnes

Additionally can see that even adding all this stuff to the German tank tonnage only brings us to about 1.2 million tonnes of German anti tank vehicle. That still leaves an Allied tank weigh advantage of about 3.74 to one, without considering allied supporting vehicles at all.

428,106.35 tons all turned into Stug III becomes 17,837 vehicles, a DECREASE, because the Marders and Hetzers are so much lighter and the heavy stuff not numerous.

771,445.4 tonnes of German tanks could become 32,143 Stug III, an increase in 10,150 vehicles on a purely weight basis. In reality the gain would probably be bigger, but the fact that each Stug still needs a pretty serious engine and transmission and gun limits how economical spamming ever really can be.

Note that a Late model Panzer IV was about twice the cost of a Panzer II and 20% more then a Panzer III, but a Stug III was about 70% of the cost of the Panzer IV. Nazi economics mean these costs are not fully accurate, and they varied by model, but they do provide useful comparison. An assault gun was not a colossal bargain if it was going to be just as heavy as tank and basically have everything a tank did except a turret ring and drive. That Germany had so many small tank plants was not going to help matters, and the need to disperse component work to avoid air raids a further hindrance. One must also consider that no matter what was built the large late war German surge in production involved entirely new factories and large increases in labor forces, all of which took time to become efficient. Germany often lacked dedicated tooling, and that made it much harder to train new workers to do anything useful. Never mind the use of kidnapped children as workers by wars end.

***

For another time to complete.....

Quickly browsing some allied production figures , you could add at least 35,000 comparable Soviet light tank AT/SP vehicles and the US M3/5 series light tanks alone are over 20,000 hulls, including some with 75mm howitzers I ignored, and all of them far superior tactically to a Panzer II or the really improvised tank destroyer conversions like early Marders I don't think are worth counting, for the same reason I'm not counting the T-28 or T-35. Throwing in the 37mm gun German stuff...it's not worth the time and much that got destroyed or converted anyway. This is not counting a lot of US self propelled field artillery, that was suffice to say, a lot more numerous then the uncounted German self propelled field guns too. The German artillery stuff is only like 1,500 vehicle max anyway and most were lightweight Wespes.

So...end of the day... pretty much 200,000 decent allied tanks and tank destroyers were out to fight about 42,500 comparable German vehicles from 1941 onward, and that's still ignoring some German losses in the 1940 campaign and a bunch of British tanks. That's a 4.7 to 1 advantage in numbers, and any attempt by the Nazilovers to suggest this or that captured piece of French junk was going to matter by 1944 is just crazy.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-03 06:41pm

Zinegata wrote:Excellent charts. I've long been a naysayer of the "Steel Panthers" model of gun penetration vs armor comparisons, as it presumes that a high-energy collision between an anti-tank shell and tank armor is a simple integer comparison with a binary result of "tank penetrated & destroyed or tank bounced shell with no consequence". In reality the collision carries enough energy to be comparable to a bunch of cars crashing into each other, and we all know that such collisions don't exactly leave the cars completely intact even if the drivers survive.


It certainly was possible to have a armor plate that would reject an enemy shell with minimal damage though, it's just such advantages tend to be very short lived. Proof conditions for armor usually assumed a decent number of shots into each plate before it would breakup, usually around five hits near the ballistic limit. That's where thick heavy tank armor did in fact have advantage...but it was against the 37-45mm gun spam Europe was filled with in 1940. Against that sort of hard to detect and counter spam fire a Tiger tank or Char B could not easily be shot to pieces. Against 3in bore guns and greater well, I think technology has always wanted us to build 90 ton tanks since the get go.


Also, I have to note that tank enthusiasts pay relatively little attention to the concept of zones and angles of immunity - something that's looked into much more deeply when it comes to battleships - in favor of simply presuming frontal hits all of the time. In reality getting hit in the front was uncommon - for the simple reason that the majority of the tank's surface area is not the front plate and that ground combat involves far more situations where an unspotted enemy initiates an ambush.


Battleships had a much higher chance of exploiting it in action is why that is. Tanks well, it does vary a great deal, in WW2 they also had to contend to possible shatter gap problems making certain range bands less effective then others thanks to poor ammunition design. The US had the best naval ammo in the war, but some pretty bad anti tank projectiles at times, because they were all designed from scratch suddenly starting in 1940 and tested against fairly soft armor.

[quote]
As an example - the German fanboys and bad Hollywood movies keep assuming that the Tiger I had an awesome front plate that was immune to most Allied tank fire. In reality when somebody tried to simulate the Fury engagement the Tiger died to the first Sherman volley because even the 75mm had a chance of going through the front plate at under 500 meters; and the SUPERIOR GERMAN TIGER COMMANDER decided that the best way to engage three charging Shermans was to charge right back at them head-on to make the range vanish at twice the rate it should have.[/quote

The 75mm only has a chance with HVAP though, and the decision was made not to mass produce that round in favor of putting focus on getting the 76mm M93 round out in a more useful quantity, since that had a little capability against the Panther too. Last I heard at most a handful of experimental rounds were sent with Jumbo Shermans.

Of course conversely the US always had a vast supply of ignored 90mm guns on hand in several hundred anti aircraft battalions in the ETO which seldom, but sometimes did engage tanks, and had the Tiger been more of an actual problem more effort could have gone into pushing them to the front lines. These units always had it in the doctrine and training to engage tanks and killed a number in the Battle of the Bulge. While the US carriage designs weren't ideal for ground action it's not like the 88mm Flak 18 really was either, and Germany was weak on artillery and air power that might counteract them. That's one of those spots where German reliance on direct fire weapons breaks down in a manner as to seriously impede the entire flow of battle.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Zinegata » 2017-01-03 11:23pm

Sea Skimmer wrote:It certainly was possible to have a armor plate that would reject an enemy shell with minimal damage though, it's just such advantages tend to be very short lived. Proof conditions for armor usually assumed a decent number of shots into each plate before it would breakup, usually around five hits near the ballistic limit. That's where thick heavy tank armor did in fact have advantage...but it was against the 37-45mm gun spam Europe was filled with in 1940. Against that sort of hard to detect and counter spam fire a Tiger tank or Char B could not easily be shot to pieces. Against 3in bore guns and greater well, I think technology has always wanted us to build 90 ton tanks since the get go.


Sufficiently heavy armor could of course absorb lots of hits, but aside from potential minor damage from each hits there's also the very real question of whether or not the crew is going to sit there and take it. There are only a tiny handful of engagements where a lone monster tank took on dozens of hits and kept on fighting anyway. Not every tank crew is like Billotte's at Stonne.

The 75mm only has a chance with HVAP though, and the decision was made not to mass produce that round in favor of putting focus on getting the 76mm M93 round out in a more useful quantity, since that had a little capability against the Panther too. Last I heard at most a handful of experimental rounds were sent with Jumbo Shermans.


I think you mean the M61 APCBC for the 75mm rather than the HVAP. The HVAP is the improved 76mm anti-tank ammo, which was issued mainly to TD units but as mentioned in the other thread was too busy being indirect-fire SPGs to do much anti-tanking anyway. Both the M61 and HVAP were indeed sparingly issued to US tank crews, but the Soviets apparently got them in spades which is part of the reason why they liked the Sherman so much.

Also the standard 75mm ammo and the APCBC was capable of around 100mm of penetration when the engagement range is under 500 meters - the APCBC's main advantage being it retained energy at longer ranges. If we go by the old penetration vs armor thickness model the Tiger might seem immune with its 120mm front plate, but in practice a couple of Tigers were taken out in 1943 by 6 pounder guns (before the APDS which pumped penetration to 140 mm) with equivalent penetration and energy; and at least one of that was with a hit from the front arc.

That's why keeping to the stand off range of 600 meters was pretty vital for the Tiger. Bad US ammo meant that its power was considerably less at that range so the chances of a damaging hit were reduced. The British 6 pounder had similar range issues. But the German fanboys all want their Tigers to charge into point-blank range like Wittman and ignore the fact that his Tiger absorbed maybe two hits at most (one of which may have been just an HE shell) before getting knocked out.

Indeed, charging your Shermans at Tigers to close the range - which was apparently advocated in the FM - may not have been that bad of an idea if you math it out. With a 30 kph speed the Sherman can close 500 meters in just one minute. Trouble is finding crews brave enough to risk that minute with 88 shells streaking towards them!

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Zinegata » 2017-01-03 11:43pm

Sea Skimmer wrote:So the allies produced a mere 6.566 times more serious tanks then Germany did, or to point it another way Germany could put one tank directly against every allied tank until the Allies still had 122,471 other medium-heavy tanks left! The battle weight advantage is 5.81 to 1 in Allied favor.


Whatever the final score of the game, Germany, the country, loses the war. :D

Now the inevitable....but Supercasematecladspanzerwaffenwerethevictory! Is sure to be employed by the lame and nazi contaminated, even though the entire point of this comparison is that German Doctrine in favor of mobile warfare was correct, and the only way for Germany to win relevant victories! That means the '100% Stug' strategy so often promulgated as the solution to Germany AFV production is simply not sound.


Germany wasn't going to win all-Stug, but it was still saner than producing Panther-bunkers. At least the Stug could move, and it could turn faster than German tanks that decided to go with hand-cranked turrets.

Also, there was the real issue of armored vehicle shortage at the Infantry Division level. A US Infantry Division by 1944 basically always had a Sherman battalion attached to it, which is 60+ tanks. That was usually complemented by a TD battalion, which was potentially another 40+ armored vehicles. The Brits had about a brigade of tanks for every Infantry Division by '44, so the armored level support was comparable.

A German Infantry Division by contrast - even the top-line ones - generally only had one company or battery of self-propelled anti-tank vehicles;. And it was usually open-topped stuff like Marders! Some Divisions also had Stummels and other hodge podge vehicles but they weren't exactly going to live long against Shermans either. They were simply being buried by Allied organic tank support even before we start counting the artillery and air power.

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby BabelHuber » 2017-01-04 12:27pm

Sea Skimmer wrote:Note that a Late model Panzer IV was about twice the cost of a Panzer II and 20% more then a Panzer III, but a Stug III was about 70% of the cost of the Panzer IV. Nazi economics mean these costs are not fully accurate, and they varied by model, but they do provide useful comparison. An assault gun was not a colossal bargain if it was going to be just as heavy as tank and basically have everything a tank did except a turret ring and drive.


As far as I know, the big numbers of Stug III which were produced can be explained by the fact that the Panzer III couldn't be equipped with a 7.5cm gun. The 5cm gun of the Panzer III was too weak to fight tanks like the T34.

So this gives the Nazis 2 choices: Either retool the Panzer III factories to produce Panzer IVs (which takes time they didn't have) or use the Panzer III chassis to produce Stug IIIs instead (which can be equipped with a 7.5cm gun).

This may not be 100% accurate, since later also the Stug IV was produced - seemingly the Nazis loved their assault guns, to the point where regular tank units received Stugs as tank replacements sometimes.

But all factors considered, using the Panzer III chassis to produce Stugs instead of retooling the factories probably was not the dumbest thing to do - even if Germany would have preferred "real" tanks, a Stug III now is preferable to a Panzer IV one year later.

As a sidenote, I find it hilarious that there are so many trolls who honestly believe that Nazi Germany would have been able to win a war of attrition.

Granted. there are some crazy documentaries on TV which state insane stuff like that the Ho 229 could have made a difference, or that Germany would have won the war if Hitler hadn't stopped his tanks in front of Dunkirk in 1940. I can even understand that (some?) people who are unfamiliar with the details of WW2 believe such nonsense.

But after digging deeper, any halfways intelligent person should soon recognize that the Nazis simply couldn't win the war they started.
Ladies and gentlemen, I can envision the day when the brains of brilliant men can be kept alive in the bodies of dumb people.

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-04 11:43pm

Zinegata wrote:Sufficiently heavy armor could of course absorb lots of hits, but aside from potential minor damage from each hits there's also the very real question of whether or not the crew is going to sit there and take it. There are only a tiny handful of engagements where a lone monster tank took on dozens of hits and kept on fighting anyway. Not every tank crew is like Billotte's at Stonne.


A lot of battles involved a lot of tanks successively taking several hits though, with heavy tanks that was less likely to add up to large numbers of writeoff vehicles. One advantage of the squishy Sherman armor though was it was reasonable to conduct heavy battle damage repair on it. This doesn't really work with face hardened armor if it does get wrecked. The Tiger suspension was really resistant to gunfire as well, but of course this directly linked to how hard it was to maintain for normal running.

I think you mean the M61 APCBC for the 75mm rather than the HVAP.


No even the vastly improved M61A1 would only penetrate a maximum of about 90mm of armor, and only then at 100 yards. At 500 yards penetration is down to about 80mm, I am looking at the proper and actually accurate 1945 era curves now. Do not be fooled by 1942 BS data. That is the great scandal of the Ordnance Corps in WW2, not that they didn't push the 90mm gun hard enough! The 75mm tank was really not capable of defeating actual 1942 Tigers front the front. German armor was erratic, actually they demanded specs far above those of the US for armor and ammo quality for land forces, but it could be really damn good at least to the mid war point. The total implosion is only a late 1944 thing.

On paper the original 75mm M72 shot used in the Western Desert (if ever produced to spec, about none was, emergency product) might perforate the front of a Tiger at about 300 yards, but realistically it was about 100 yards to inflict any reliable internal damage, and only on part of the front plate, on maybe a good day, otherwise the M72 shot might be totally rejected with little damage. Also this round wasn't really issued later in the war, due to its known horrible quality problems. This projectile was so bad about 15,000 were replaced in Egypt with captured German 7.5cm shells to give the British something better quickly.

Earlier ballistic trials were conducted against targets softer then actual German tank armor. The problem is while the improved Sherman ammo was better against the face hardened Panzer III/IV and Tiger, it still wasn't tested against something like the front of the Panther, and would just breakup or detonate on impact. Also most tests were made not on captured Tigers, of which we had almost none, but surrogate armor back in the US by people who had never seen a Tiger. The 75mm Shermans had basically no chance against the front of those two German tanks. It was worth firing back, but, good luck. The M61 rounds had HE fillers and would tend to detonate on impact. It was such a problem the fillers were removed from some rounds in the field (ordnance corps officers made a lot of field ammo mods in the war). M61A1 had a more reliable base fuse.

HVAP is a class of ammo, not a specific round, all original work was done in 37mm. The US never applied it to 57mm because British 6pdr APDS already existed, but in the 1944 Panther emergency the US Army threw 76mm and 90mm HVAP rounds into production. A small amount of 75mm HVAP T45 was also produced, but not adapted as limited standard due to shortages of material and machines, and low overall effect. Supposedly some of the left over trial rounds were forwarded to Jumbo Sherman units, as that had also been an Ordnance pet project. This could kill a Tiger at 500 yards, but still not much use against the Panther.

The 76mm HVAP started as T4 and became M93, but originally some tens of thousands of early production rounds were rushed to the battlefield starting in August 1944 or so. The M93 standard only arrived in early 1945. This could cope with the Tiger well but still had serious problems against actual Panther targets past 450 yards or so.

Both the M62 and M79 rounds for the 76mm also had considerable problems with the Panther but could decently handle the Tiger from the front, but on an erratic basis that caused alarms in Normandy. With all this ammo it was was never tested to not breakup, as maximum proof angle was 30 degrees. This is why British ammo broke up at Jutland sometimes, it was never tested in proof conditions like it was hitting. IIRC some M79 rounds were reheat treated in Europe, and reissued, but the performance gain was low. The undermatching caliber issue did not help, the German plates being thicker then the shells even for the Panther bow.

The 90mm with its M82 APHE round, and any other AP round, would handily kill a Tiger, and really really kill it while it did so, at a range of over 2,400 yards. But it and the the initial 90mm rounds T30 HVAP round had the same problem of the 76mm guns against actual sloped armor targets like the Panther, it would just breakup too easily. Rejection would not happen with tungsten.

For win the M82 would penetrate the angled side of the Panther at 5,850 yards!

Still the failure of the T30 HVAP to be reliable against the Panther caused a SUPER PANIC, which led to the T33 HVAP round specifically for that purpose. It would kill a Panther anywhere at 1,100 rounds, and was the first time the Ordnance Corps really supercharged one of these rounds, as opposed to designing the ammo for high barrel life. This is also what spawned the super giant Pershing 90mm mod.

The T30 was actually better against the King Tiger, which used sorta face hardened armor, and could penetrate the glacis at 100 yards. It penetrated the glacis of the Panther at 450 yards, and the respective mantlet and turret of both at 800 yards.

Mind you the spread on HVAP penetration data is so wide they didn't bother to give it as a curve, but as a V90 band on the graphs. Postwar the US quickly adapted a 60 degree armor target standard, and that's how we get the transformation of the 76mm gun and ammo on the Walker Bulldog tank from 1953 could kill King Tigers easily. German HVAP style ammo in the war was best, but it also by far consumed the most tungsten per projectile, which was why Germany had to stop making all the stuff. Their 50mm round, which the US got samples of in 1941 via the British, had something like 50% more tungsten relative to its own caliber then any of the Allied rounds. That adds up fast!

The longer 90mm T15E1 on the Super Pershing BTW could fire all the normal 90mmprojectiles, but on bigger cartridges. IIRC it also had a specal supershot HVAP only it could fire. \

[which was issued mainly to TD units but as mentioned in the other thread was too busy being indirect-fire SPGs to do much anti-tanking anyway.


That was mostly an Italy thing, the theater was largely deprived of army level artillery. Prewar the Army had planned to have a 3in field gun to make up for the low range of its divisional 105mm howitzer, but killed that to have men to crew all these new anti tank guns additional anti aircraft pieces. The difference was 14,650 against 11,000 yards, pretty considerable. So side job of the M10 as a long range gun was natural, it was never detracting from the anti tank role in any relevant sense. Later in the war the US Army began giving 75mm tanks the sights for indirect fire too, and this was standard postwar equipment until the M1 tank. We had 105mm and 155mm ammo shortages in the Winter of 1944, and went so far as to fire captured German 105mm ammo after remanufacturing the driving bands at Paris workshops. Getting more small caliber guns into action, for which ammo supplies were large, was important.

That's BTW a place where the not ideal but logical 1940 era Ordnance decision to produce all guns and ammo for long barrel life suddenly paid off in dead Nazis. If all the barrels got worn out by spam fire we might have had an actual problem.

Both the M61 and HVAP were indeed sparingly issued to US tank crews, but the Soviets apparently got them in spades which is part of the reason why they liked the Sherman so much.


BS. M61 was standard. No HVAP went to the USSR, period, as far as I can tell. In fact the Soviets got a shitload of the M72 shot that sucked for their M3s and M4s, but most of it at a time when a lot of German tanks were still the freaking Panzer II or similar junk that was vulnerable to just about anything you could fire. Just to repeat, no HVAP was being produced at all before July 1944 when emergency calls from Normandy came, because the 3in gun had problems against actual German tanks.

The US did deliver tungsten meta to the Soviets, but it was up to them what they used it for. 76mm HVAP production was never over 6,000 rounds per month, and it began to run down by 1945 to allow for much more 90mm production.

Indeed, charging your Shermans at Tigers to close the range - which was apparently advocated in the FM - may not have been that bad of an idea if you math it out. With a 30 kph speed the Sherman can close 500 meters in just one minute. Trouble is finding crews brave enough to risk that minute with 88 shells streaking towards them!


You also need ground open enough to do so, and the enemy not to be positioned such that this will give his supporting fire flanks shots on your hulls. The field manuals for this subject say many things, charging to close with a superior enemy is a tactical option they wanted a commander to know was acceptable. But they also wanted you to use your damn recon units, all those light tanks, aggressively to find the enemy first, rather then blundering your main body around looking for a frontal fight. Use of recon is like cancer to movies and games, but rather utterly integral to the whole blitzkrige idea. Lead the advance with a recon unit, back it up directly with an anti tank unit, only then have your tanks coming up ect.

The problem is when you can't flank the enemy due to force density and constricted or heavily fortified avenues of approach, but by nature that is almost always a far more complex situation then just tank to tank.
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-05 12:34am

Zinegata wrote:Germany wasn't going to win all-Stug, but it was still saner than producing Panther-bunkers. At least the Stug could move, and it could turn faster than German tanks that decided to go with hand-cranked turrets.


Pah the original OT spec Panther bunker with its two piece 70mm thick steel bunker box and total metal mass of over 41 tonnes is amazing! But in October 1944 a new super amazing design you could mount on WOOD appeared, as did the concrete base one, and I had forgotten but both of those had two DIFFERENT methods of power traverse! At 6 entire degrees per second, but that beat 3 degrees maximum hand cranking, without having the loader man an auxiliary wheel for slightly more speed.

All models had an electric fan marvel so the gun fumes did not kill everyone.

I've read some of the Italian action reports though, as most of these went into the Gothic Line, and a group of Panther turrets was absurdly hard to take out with a tank attack, and pretty well immune to anything short of WW1 scale artillery bombardments. Panther turret production outran the hulls at times, so this wasn't a total waste. What gets really crazy is in 1944-45 they began mounting large numbers of 88mm and 75mm tank guns on basically open pivot mounts attached to logs. No tank to mount gun on, but they could shoot and actually had a better field of fire then some towed guns. It was just...not moving again.

All of this though was done heavily with obsolete tank guns and turrets for anti invasion work, a shitload of the stubby 50mm guns and Panzer II turrets went to service on this way.


BabelHuber wrote:As far as I know, the big numbers of Stug III which were produced can be explained by the fact that the Panzer III couldn't be equipped with a 7.5cm gun. The 5cm gun of the Panzer III was too weak to fight tanks like the T34.


The Stug has nothing to do with the T-34 originally. The Stug is a prewar project, and while it it had merit its origin is super tied into Nazi-Heer politics, the artillery branch did not want to be left out of mechanization, and the infantry wanted assured support, and naturally opposed Panzer divisions. Meanwhile the Heer cavalry also demanded their own mechanization, which is how those stupid Light Divisions appeared. The Stug was to be specifically a infantry close support weapon, something the Germans had gotten really fond of in 1918 tactics. Its advantage was in part that yes it was cheaper, but mainly the point was it was low...and it was different.

This ensured that at a strategic doctrinal level Germany had chosen to dilute its mechanized power. And instead of diluting it towards long range mobile artillery that could mass fires, it diluted it towards close support. This was really not a good plan, but I'm afraid the true implications are the sort of thing that goes right over the head of the typical German armor fans, and most writers too. Blitzkrige was using air support to fill in the gap this made...people just utterly fail to grasp what it meant when the Germans lost that bomber support, distinct from if they had any defensive fighter coverage or not. They destroyed their damn bomber forces by forcing unsuited twin engine aircraft into CAS roles too (as opposed to interdiction), it died off from that as much as from Hitler randomly ordering ALL PLANES ON LONDON.

The Light Divisions were progressively enlarged into actually useful Panzer divisions, but only after a lot of trouble. The Stug production though became very self perpetuating. It did not have to exist at all.

Something to consider too, a Panzer IV carried twice the ammo a Stug did. The low profile of the Stug didn't leave much space for shells. Cheaper, but certainly less combat power too. The Panzer III actually could take the short 75mm, the late models had it, but the ammo supply was not amazing and it was cramped. The HEAT round for this gun actually could kill the T-34, but with the usual WW2 HEAT limitations.

So this gives the Nazis 2 choices: Either retool the Panzer III factories to produce Panzer IVs (which takes time they didn't have) or use the Panzer III chassis to produce Stug IIIs instead (which can be equipped with a 7.5cm gun).


When it was 1942....sure.

At the time the Germans began building the Stug III though they had almost no Panzer III tanks in the first place! Like 160 in total or something similar was all, and the main Stug III plant was not the original Panzer III plant, it began building both at the same time. But what then became even more crazy is yeah, they used Mark IV hulls when Stug production was failing to expand as desired, Guderian was pissed at this even as inspector of panzer troops in the mid war period he was denied control over the assault guns because of interservice rivalry (he claims anyway). Again, it was a dilution of power, and one that made it harder and harder to actually employ German armor to good effect because units were not tactically interchangeable.


As a sidenote, I find it hilarious that there are so many trolls who honestly believe that Nazi Germany would have been able to win a war of attrition.
[/quote]

Yeah...details. The problem is all the 'my pah said' stuff that came from an era without details. Germany had formally reduced the caliber of its infantry divisional artillery to 75mm by the time 1945 hit, meaning a reversion to 1914 levels of firepower. A real great sign for victory in six more months!
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Zinegata » 2017-01-05 01:35am

Sea Skimmer wrote:That was mostly an Italy thing, the theater was largely deprived of army level artillery.


I believe Nick Moran - who's plotting to do a Tank Destroyer book while not doing research for WoT - actually had a look at the overall ammunition usage and found indirect fire was used five times more than direct-fire overall. Italy was where they started doing it in '43, but Italy couldn't have accounted for all those indirect fires.

Pah the original OT spec Panther bunker with its two piece 70mm thick steel bunker box and total metal mass of over 41 tonnes is amazing! But in October 1944 a new super amazing design you could mount on WOOD appeared, as did the concrete base one, and I had forgotten but both of those had two DIFFERENT methods of power traverse! At 6 entire degrees per second, but that beat 3 degrees maximum hand cranking, without having the loader man an auxiliary wheel for slightly more speed.


Wait, the Panther turret bunker was seriously 41 tons? When the actual bloody tank was 45?!

I've read some of the Italian action reports though, as most of these went into the Gothic Line, and a group of Panther turrets was absurdly hard to take out with a tank attack, and pretty well immune to anything short of WW1 scale artillery bombardments.


But so are sufficiently thick concrete bunkers, which is why they threw 155 SPGs at bits of the Sigfried line..

At the time the Germans began building the Stug III though they had almost no Panzer III tanks in the first place! Like 160 in total or something similar was all, and the main Stug III plant was not the original Panzer III plant, it began building both at the same time. But what then became even more crazy is yeah, they used Mark IV hulls when Stug production was failing to expand as desired, Guderian was pissed at this even as inspector of panzer troops in the mid war period he was denied control over the assault guns because of interservice rivalry (he claims anyway). Again, it was a dilution of power, and one that made it harder and harder to actually employ German armor to good effect because units were not tactically interchangeable.
[/quote]

Guderian kinda warmed up to the Stug eventually. What drove him up the wall was how they had a Stug based on the Panzer IV chassis and the Jagdpanzer IV. Casemate vehicles for everyone! OTOH since they went back to hand-cranked turrets by the Panzer IV J it wasn't really going to make much of a difference.

And in any case the reason why the Stugs were so popular was due to the armor shortage issues I mentioned in the regular Infantry Divisions. The Panzer Divisions basically took all of the tanks and very rarely operated with non-Panzergrenadier infantry, because they were imbued with the idea that they should operate independently from the foot-slogging infantry. Hence you have maybe a company of armored vehicles for every German Infantry Division if they got lucky, compared to entire battalions per infantry Division on the Allied side.

The only armor support that regularly fought side-by-side with regular German line infantry Divisions were the Stug battalions, which made them very popular among the rank-and-file Landser and why there was a constant demand for more Stug battalions. Indeed, if I recall correctly the shift to Mk IV hulls was actually triggered by the bombing of the main Stug III plant - which nearly caused Stug production to be cancelled altogether until the frontline people basically demanded it be brought back!

The issue really is that while Germany could only win by concentrating everything in Panzer Divisions doing maneuver warfare, complete victory was beyond their grasp by '43 and '44 anyway. By 1944 in particular the Allies were already able to match the Panzer Divisions head-on in maneuver battles; even in battles where fog deprived the Allies of much of their air and artillery support. Dompaire and Arracourt in particular demonstrate what happens when the German Panzer commanders pretend it's still 1941 and they can just drive around at-will.

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Simon_Jester » 2017-01-05 03:55am

Zinegata wrote:
Sea Skimmer wrote:That was mostly an Italy thing, the theater was largely deprived of army level artillery.


I believe Nick Moran - who's plotting to do a Tank Destroyer book while not doing research for WoT - actually had a look at the overall ammunition usage and found indirect fire was used five times more than direct-fire overall. Italy was where they started doing it in '43, but Italy couldn't have accounted for all those indirect fires.
I'd expect that indirect fire would tend to consume a lot of the ammunition.

I mean, correct me if I'm wrong, but a typical direct fire mission is something like "shoot at that tank until it's on fire," and you can see when you've accomplished that goal. Most of the time, it won't take more than a few shots to accomplish the goal, too- unless you've made a serious mistake by opening fire in the first place.

By contrast, a typical indirect fire mission is "fire twenty rounds into this square on the map." You go through a lot more ammo, and you can't actually tell when you've succeeded. At best, you have infantry spotters who have absolutely zero incentive to tell you to cease firing until it's time for them to physically occupy the position you're shelling. From their point of view, the more rounds you put in and around the target, the better.

So unless the concern is that the tanks are wasting ammunition or wearing out their barrels with indirect fire, I don't see the problem. If tank destroyers spent 50% of their time on indirect fire missions, and 50% of their time on tank-hunting missions, that would still involve most of the shells actually fired being used up while impersonating an SP artillery piece.

Wait, the Panther turret bunker was seriously 41 tons? When the actual bloody tank was 45?!
If the steel box underneath the turret was seventy millimeters thick, it was significantly heavier and thicker than the actual side armor of a Panther tank. That might have contributed.

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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-05 03:48pm

Zinegata wrote:I believe Nick Moran - who's plotting to do a Tank Destroyer book while not doing research for WoT - actually had a look at the overall ammunition usage and found indirect fire was used five times more than direct-fire overall.


How he determining that? Ammo use was something like 10:1 infavor of HE, but a great deal of that was expended in direct lay combat because the Nazi tank supply was very low day to day. The M10s in Italy though were kept parked full time in the indirect fire positions, since like any mobile anti tank asset you didn't want them in the front line if you weren't advancing.


Italy was where they started doing it in '43, but Italy couldn't have accounted for all those indirect fires.


It actually started outright in North Africa, and the procedures including how to TOT coordinate with regular field battalions were invented in the field there. It then spread to all battalions in Italy, and became standard training for all tank and tank destroyer battalions in the Army in November 1943. Prior to that they were giving a short course on basically 'this is how a collimator sight works'.

The Italian fighting went on much longer, and on a much more consistent basis then the north western europe fight, they also used large numbers of 90mm anti aircraft guns in the indirect fire role in that theater, once Naples was rendered secure from Nazi bombing by that giant smokes screen of doom, and the shooting down of all the Nazis outright. Maybe it didn't consume the actual majority of missions, but it was extremely ammunition intensive as a campaign. 3in never had an ammo shortage, while 82mm and 105mm did, the otherwise two prime close support calibers. So that really spiked 3in consumption at one point, at least as much as they could exploit it. But this was never going to be allowed to detract from the anti tank role if any damn tanks appeared.


Wait, the Panther turret bunker was seriously 41 tons? When the actual bloody tank was 45?!


Image

Image
Image

The original proper win one was, the concrete was optional if you wanted it. This also meant it would withstand incredibly heavy artillery bombardments and air bombing because its box is able to withstand the very near miss blast-frag of anything short of 12in howitzer shelling or air bombing. Direct hits would need to be over 155mm, and indeed probably over 8in if only an HE round (as opposed to specialist ammo) to destroy it. That's not a joke when the damn thing iss o hard to hit.

The weight is also important in that respect to anchor it into the ground in the event its attacked by stuff like 100-1000lb bomb carpet bombing the allies would employ against tactical targets. At a certain point big enough bombs vs limited mass fortifications risk physically displacing the fortification. But the odds of bombing something this small, or even getting air missions assigned to try, was very low.

Not many of these armor win boxes got built, not because Hiterlism judged the use of steel to be poor but because it turned out to be too hard to install the armor box, which was two main pieces, in the field with limited mechanized equipment. They had hoped this would be easier then setting and pouring reinforced concrete but it functionally wasn't unless the site was very near a railroad, which some naturally were. The turret itself is only 8 tons and not hard to move and emplace.

Also it was plausible to remove the entire metal box mounting for strategic deployment. MOBILE FORT!

The later ones were on thin reinforced concrete, which was pretty good protection but wouldn't stand up to direct hits bigger then 155mm. Since the turret wouldn't anyway that was okay, and points to the advantages of physically small but weak fortifications on an actual battlefield. Hybrid types also existed. The basic log mount shows how the 75mm recoil wasn't too big a deal, and could still hold up to a lot of fire. Certainly they could fight while being shelled far better then towed guns or any kind of open roof SP mount.

Image

If you just wanted the damn turrets to work a log bunker could and would work and still offer you the advantage of a very low profile, but not nearly as much protection from vertical fire.


But so are sufficiently thick concrete bunkers, which is why they threw 155 SPGs at bits of the Sigfried line..


No this is not really interchangable with concrete, and while almost none of it was finished the 1940 the Westwall was going to have a shitload of turrets, and a lot of casemates that made use of very large armor pieces and fixed cloches. And the Maginot line, which on a bunker for bunker level was way more powerful then anything Germany finished, was just loaded down with turrets and armor too. That's why it cost so much. Germany never took on one of the major forts.

Turrets mean that 155mm gun attack? That doesn't work. The 155mm direct fire is only good at maybe 1000-2000 yards, and at that kind of distance a Panther gun would kill the 155s first. The direct fire vulnerability of bunkers is precisely why they needed turrets. Otherwise they will always have giant blind spots, they MUST be sighted to flank fire or they are suicidal, and concrete is vulnerable to breaching fire. Bunkers made of 2.5-3.5m thick concrete could stand up to a lot of breaching fire, but they ended up as physically huge targets and were impractiable to build anywhere near a combat zone. Also they still consume large tonnages of steel for all that rebar.

That huge problem is what really killed off the Maginot ideal.

In contrast a group of Panther turrets added to existing field fortification systems creates a wide web of anti tank fires with overlap. It's not something you use one at a time or place.

The Panther turrets were very successful within the limits of any fortifications, and basically the only thing that was worth building, many tank turret fortifications were built before and after them, including into the 1980s by Austria and the Swiss, though most people stopped in the mid 1950s when ATGMs appeared. At least two T-72 turret bunkers have been built in Iraq, one of them on top of a building.

Guderian kinda warmed up to the Stug eventually. What drove him up the wall was how they had a Stug based on the Panzer IV chassis and the Jagdpanzer IV. Casemate vehicles for everyone! OTOH since they went back to hand-cranked turrets by the Panzer IV J it wasn't really going to make much of a difference.


He was still moaning about it at least past the collapse at Normandy. Even a hand cranked turret beats no turret, as you can still turn the vehicle to help speed this up. The Stug has a really narrow field of fire as it was.


And in any case the reason why the Stugs were so popular was due to the armor shortage issues I mentioned in the regular Infantry Divisions. The Panzer Divisions basically took all of the tanks and very rarely operated with non-Panzergrenadier infantry, because they were imbued with the idea that they should operate independently from the foot-slogging infantry. Hence you have maybe a company of armored vehicles for every German Infantry Division if they got lucky, compared to entire battalions per infantry Division on the Allied side.


Yup, but even the Stug units tried to avoid themselves being reduced below battalions, and Germany could have formed more tank battalions or produced more duel purpose SP vehicles with 105mm weapons from the get go. Small numbers of armored vehicles are just not very effective, what limited the Tiger ect... limits any AFV in small groups. Just too easy to be ambushed, no ability to maneuver against the enemy except very defensively.


The only armor support that regularly fought side-by-side with regular German line infantry Divisions were the Stug battalions, which made them very popular among the rank-and-file Landser and why there was a constant demand for more Stug battalions. Indeed, if I recall correctly the shift to Mk IV hulls was actually triggered by the bombing of the main Stug III plant - which nearly caused Stug production to be cancelled altogether until the frontline people basically demanded it be brought back!


At one point it was also proposed to stop making the Mark IV tank. A lot of less then sane thing were thrown around, but fact remains German production kept diverging on types and the Stugs created this whole different avenue of demand that then had to be managed. Of course people will demand more of everything that kills Russians, but we are talking about a vehicle consumption that otherwise could have formed entirely new panzer corps. That's a really big deal when say in 1943 Italy Germany only had two. Win the war no, but just maybe it might have won some major battles.

The issue really is that while Germany could only win by concentrating everything in Panzer Divisions doing maneuver warfare, complete victory was beyond their grasp by '43 and '44 anyway. By 1944 in particular the Allies were already able to match the Panzer Divisions head-on in maneuver battles; even in battles where fog deprived the Allies of much of their air and artillery support. Dompaire and Arracourt in particular demonstrate what happens when the German Panzer commanders pretend it's still 1941 and they can just drive around at-will.


Those battles really only illustrate my point, thanks to them involving another brilliant dispersion of effort that was the German formation of independent panzer brigades late in the war. These units only had one tank battalion, and the only thing resembling artillery was a battery of Stugs. Hitler thought troops would fight better in new units for moral reasons. So as a result in Arracourt the most experienced German unit had almost no tanks, while two green tank brigades with no integral support had Panthers. The entire battle of Dompaire meanwhile was on of those panzer brigades being destroyed. Of course this was going to go badly!
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-05 06:12pm

I was curious so I consulted that official US munitions guide,and actual 3in Army production was as follows, keeping in mind this covers all uses of that gun by the Army.

HE M42A1 6,279,000 full charge, and 1,337,000 reduced charge HE rounds. It appears the reduced charge was specifically for artillery missions, and appears in mass production in June 1944

M93 HVAP 33,000, with production ceased in April 1945

M79, M62 and M62A1 AP projectiles are all grouped together and totaled 5,685,000

M88 HC smoke was 229,000 and only appeared in March 1944

T13 WP smoke was 58,000 and only appeared in March 1945.

A naval pattern illuminating round was also produced to the tune of 151,000 rounds from June 1944 onward.

So while this does not tell us how much was actually fired, the appearance of multiple types of specialist rounds late war definitely points to increased focus on the 3in gun and M10 force as a general purpose armored fire support system, also know as a tank.... The actual ETO M10 force averaged around 800 vehicles IIRC, they needed something to do!

For comparison to other arms though, the US produced 3,255,000 105mm HEAT rounds for the M2 howitzer! So don't let anyone tell you US artillery and the M4(105) did not have that ammo,they sure as hell did and it could kill Panthers.

The 105mm M2 total is 295,000,000 rounds. That isn't counting the super similar 105mm M3 howitzer ammo either, which adds 7.9 million more shells. This does include 2 million poison gas shells.

For awesome this also gives the other sort of mass production HVAP rounds! Though calls them APT.

90mm T33 was 71,000 rounds from March 1945, with about 28,000 done before Germany surrendered.

90mm T30 was 45,000 rounds from January 1945, but only 7,000 rounds finished before May 1945

90mm T44/45 for the special long 90mm gun was 20,000 rounds from May 1945.

So HVAP was rare but it sure outnumbered the German tanks! If the war had gone on even one or two months longer several tens of thousands more HVAP rounds would have hit the field.

Also JUST IN CASE the 75mm Shermans were really in deep shit, they had 589,000 poison gas shells with three different types of filler their guns could totally fire built and stocked, thanks to it sharing ammunition with certain artillery weapons. Those puny King Tigers don't have sarin gas rounds, on to Berlin!
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Re: WW2 Tank-Anti Tank Gun Muzzle Energies

Postby Sea Skimmer » 2017-01-09 12:19am

Since it seems to remain obscure on the internet, I have digitalized the specs for the 75mm HVAP from paper based material sources.

***

75mm HVAP T45 Shot (APCR-T)
Cartridge Weight -13.50lb
Projectile Weight - 8.4lb
Velocity when Fired from 75mm Gun M3 and M6 - 2,850fps (869mps)
Maximum Powder Chamber Pressure 38,000psi

Muzzle Energy (my calculation) - 1,441,827 joules

Penetration of Homogeneous Armor at 30 degrees obliquity
4.6in (117mm) @ 500 yards
3.8in (97mm) @ 1000 yards
3.1in (79mm) @ 1,500 yards
2.5in (64mm) @ 2,000 yards

***

We can see real easy now why this tungsten was not adapted. It does make the 75mm Sherman capable of defeating a Tiger at 1,000 yards, but this is not functionally better then the performance of the 3in gun firing steel ammo. In fact at 1,500 yards the 3in gun is already superior due to the heavier shell weight keeping up velocity.

The advantages of tungsten carbide vary depending on the actual sectional density of the projectile employed, and the actual velocity range being fired. The 75mm starts slow and US ammo always used a fairly minimal amount of tungsten, while the famous German 50mm round ensured its own demise by having exceptionally high density, and thus strategic tungsten consumption.
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