Which has a more potent anti-tank gun the Sherman 76mm to the Russian t-34-85

[Hannibal]

I have seen conflicting info in different games so does anyone know which has a more potent anti-tank gun the Sherman 76mm to the Russian t-34-85

[Guest jaja]

Their normal shells have about the same anti-tank penetration, but with HVAP (High-Velocity Armor Piercing) the 76.2mm is far superior.

[Tanaka]

jaja...that's a bold statement... I wonder if any other member of this forum is with you...

[Bastables]

One should remember that the 8,5cm guns also had APCR ammo, try http://www.wargamer.org/GvA/weapons/usa_guns5.html for the 7,6cm and http://www.wargamer.org/GvA/weapons/soviet_guns7.html For the 8,5cm guns.

[PzKpfw 1]

The Soviets APC & HVAP rounds were both inferior to the 76mm round carried in the LL M4A2, Ie, Performance below:

85L54.6 firing BR-365 APC-T @ 30^

500m - 91mm

1000m - 83mm

1500m - 76mm

85L54.6 firing BR-365P HVAP @ 30^

500m - 116mm

1000m - 84mm

Sherman 76mm performance:

76mm fireing M79 APCBC @ 30^

500yrds - 109mm

1000yrds - 92mm

1500yrds - 76mm

76mm fireing M93 APCR-T

500yrds - 157mm

1000yrds - 135mm

1500yrds - 116mm

This is the reason the Soviet report on the Sherman, state the 76mm had better AT performance. Another factor was the quality of US round production, compared to Soviet production methods.

Regards, John Waters

------------------

"We've got the finest tanks in the world. We just love to see the

German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. February 1945.

[This message has been edited by PzKpfw 1 (edited 11-27-2000).]

[Slapdragon]

Certainly in Korea 76mm armed E8s were considered more than a match for 85mm armed T34s even when green US tankers (prior to the arrival of USAR units) faced experienced Korean tankers (who had fought with Mao).

[kipanderson]

John, hi,

The penetration figures you give are the “official” Soviet penetration figures from the war. However the problem is that the Soviets and the Americans did not calculate penetration on a consistent basis. You cannot compare the US and Soviet figures.

At the time of writing I am looking at the section dealing with the 85mm gun in a 700 page, 1947 British Ordnance Board report. It quotes the same “official” Soviet figures but then gives this “health warning”,

“It is know that the Russians calculate their penetration of armour figures by a more pessimistic formula than that used by other powers. This results in the figures being lower than expected for the ballistics of the gun and ammunition.”

They then go on to give their own figures that are some 30% higher than the Soviet figures. It is worth remembering that you yourself were kind enough to post the results of a German test of the Soviet 76.2mm gun firing the BR350A APC projectile that show its penetration to be the same as that which one would expect from German quality ammunition. My view is that the British were a little generous with their figures. For the 85mm gun against plate at 30 degrees, at a range of 500 meters, I would go for a figure of about 105mm of penetration using the standard APC projectile. Using the HVAP tungsten core projectile I would go for a figure of 140mm of penetration against plate at 30 degrees at 500 meters range. (These are consistent basis figures using as my starting point the figures you give in your post for the US 76 gun and then assuming Soviet ammunition was of lower quality than US ammunition.)

There is no perfect answer to this question and Charles will have give it careful thought for CM2, which I am sure he will.

All the best,

Kip.

[PzKpfw 1]

Heyas Kip I was waiting for you to chime in . Yes the pen data I used is 'official'.

Kip as I'm lacking any British live fire test data from Soviet guns to go with their report's calculations, claims of a 30% increase etc, are speculation to me.

The alleged Soviet poor round quality that affected its performance, & especily HVAP rounds, I can only 'speculate' on how it affected overall performance.

Soviet ammunition was designed for ease of construction so that unskilled labor could produce it in large quanaties, while still retaining it's 'battlefield performance' the problem's some say resulted from material shortages etc. Concerning the 76mm vs 85mm the Soviet report as well on the M4A2 76mm Sherman, also states the 76mm gun had better AT performance then the 85mm S-53 etc.

Regards, John Waters

------------------

"We've got the finest tanks in the world. We just love to see the

German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. February 1945.

[This message has been edited by PzKpfw 1 (edited 11-27-2000).]

[Dan Robertson]

Kip I take it that you use the de marre formula used in this game.

Using this and the data on shell weight and Mv from the wargamer site.

I have made a spread sheet of some of the most comon guns from WWII.

Using de marre and a velocity loss formula of my own (which is not scienfic but works!)From my spread sheet 3.6 is a pretty good figure for relating t/d to energy per mm

The 85mm

MV 792 Shot 9.2 kg

Now Russian shells are meant to have better performance against slope compared to Westurn guns. However the 85 does not it seems to have a cofficeint of 1.4 like the 76mm. (this is based on the penetration figures)

The 85 should penetrate 130mm vertical at 1000meters or 112 at 30deg.

Stats say,105 and 85 respectivly

76

Mv 792 shot 7kg

should penetrate at 1000m

112 at 30

stats say 92mm.

17pdr

Mv 884 shot 7.71 kg

should penetrate at 1000m

132mm at 30deg

stats say 130.

88mm L71

Mv1000 shot 10.2

should penetrate at 1000m

175mm at 30deg

stats say 165mm

So basically the constant needs to be changed slightly for every gun. On the subject of testing the US test were possibly easier than the British but their weapon performs worse by a considerable margin.

In percentage terms.

17pdr =101.53% over

76mm =121.7% over

88mm =106% over

85mm =130% over

this shows that amunition performance needs to be taken into account. I read about a test of the 76 verses the 17pdr in which the 17pdr knocked hell out of the 76. In was noted in the test that the 76mm rounds were of poor quality compared to those of the 17pdr.

So therefor I would say that the 85mm over estimation is due to both a more demanding test criteria and also poor shells compared to the 17pdr which was premium AT weapon.

(and of course my velocity loss formula! which is based on stats from the 120 L44 firing)

and the other thing which must be remembered is that the 17pdr was pure solid shot where as the other shells have an explosive filler which degrades penetration but guarentees kill if the target is penetrated.

For an idea of what I am on about go here.

http://www.wargamer.org/GvA/background/pentypes17.html

[kipanderson]

John, hi again,

I agree that the 30% increase is likely to be speculation of a sort, i.e. examination of a number of small samples of ammunition and calculation of penetration using the formula that was current at the time. There are notes on ammunition quality and they only state that HVAP ammunition was of lower quality. They are very specific about aerodynamic shape being poor and leading to lower penetration at long ranges for the HVAP projectile. I am happy to accept that the US 76 had greater penetration but in my view probably only by a little. Remember the guys in the Ordnance Board new a thing or two about their subject and their opinions should be given reasonable weight.

Dan,

I do use the de Marre formula but not in quite the same form it is used by Charles in CM. You have produced a very full and interesting post, great work. A post that I think would interest you, and gives a very full account of my views on the penetration figures in CM, is titled “German armour penetration over stated?”. In the search engine it is normally listed under someone else’s name but is in fact one of mine. I know it is a drag to have to use the search engine but I think the post will interest you. You and I have been doing very similar work and a full account of mine is given there. Also Charles would be interested in your view of the penetration figures for the British guns. Over there he has asked that any interested parties give their opinion.

All the best,

Kip.