US Army OOB

[MarkSheppard]

If these number are right. Then the gun on the normal M26 was more powerfull but I thought the T15E1 was suppose to me a better gun with the longer barrell and all.

The gun on the normal Pershing was; from Hunnicutt's Pershing:

90mm M3 Gun Data:
52.5 Calibers

Penetration:

Early M82 APC Shot (2,650 ft/sec)
120mm @ 30 degree angle @ 500 yds
112mm @ 30 degree angle @ 1000 yds
104mm @ 30 degree angle @ 1500 yds
96mm @ 30 degree angle @ 2000 yds

Late M82 APC Shot (2,800 ft/sec)
129mm @ 30 degree angle @ 500 yds
122mm @ 30 degree angle @ 1000 yds
114mm @ 30 degree angle @ 1500 yds
106mm @ 30 degree angle @ 2000 yds

M304 HVAP Shot (3,350 ft/sec)
221mm @ 30 degree angle @ 500 yds
199mm @ 30 degree angle @ 1000 yds
176mm @ 30 degree angle @ 1500 yds
156mm @ 30 degree angle @ 2000 yds

[The_Warrior]

Ok. So do you now how they come with penetration numbers for the game? I under stand the Armor ratings. If I did it right, the modified Super Pershing should have frontal armor of 18 for the hull front and 19 for the turret front.

Art. [img]/threads/images/Graemlins/Flag_USA.gif[/img]

[sturmovik]

I was investigating the Super Pershing myself today and there are some fairly consistent penetration values for the 90mm T15E1 L73 gun, but the value seem to be a bit fantastic. Perhaps people could comment a bit?

330mm @ 30 degree angle @ 100 yds
240mm @ 30 degree angle @ 1000 yds
Panther Hull @ 2600 yds

The 90mm L73 T15E1 gun was an attempt to provide the same kind of performance as the German 8.8cm PAK 43 anti-tank gun. Like the German gun in addition to the longer barrel the gun fired ammunition with a larger propelling charge. Muzzle velocity firing the T30E16 projectile increased from 3,350fps to 3,750 and T33 from 2,800fps to 3,200fps, increasing the range at which a Panther hull front could be penetrated to 2,600 yards! Originally the T15 used one-piece ammunition but at 50-inches long it was too bulky to handle in a tank turret so a redesign was undertaken to employ 2-piece seperately loaded rounds, which became the T15E2 to be mounted on the Heavy Tank T26E4. Even with 2-piece ammunition the cartridge case extended past the turret ring during loading which could cause problems at anything other than level elevation.

http://answers.yahoo.com/question/in...8013116AAroXQM
http://www.3ad.com/history/news/super.pershing.1.htm

[Cross]

Here is the penetration according to a classified US Army document dated June 1945:



Taken from:

WAR DEPARTMENT FIELD MANUAL
FM 6-40
FIELD ARTILLERY GUNNERY
1 June 1945


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[Cross]

Here's the armour thickness they could penetrate at 30 degrees:




ps. Panther front hull is 85mm, at 55 deg it would be 148mm


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[sturmovik]

Those are for the standard 90mm L53 guns. Does anyone have info on the 90mm T15E1 L73?

[Cross]

Originally Posted by sturmovik

Those are for the standard 90mm L53 guns. Does anyone have info on the 90mm T15E1 L73?

Post #3 on this thread has penetration data for the L73, and as pointed out it performance is worse than the L53!

I looked on the internet and found 4 other sources/mentions of penetration. Out of the 5 only one (source 3) gave the L73 better penetration than the L53!

The PEN in bold didn't mention 30deg.
So source 3 would be 258mm at 30deg at 500yds, which is only 11mm better than the L53:




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[sturmovik]

Hmmm, that's odd. The propaganda clearly states that it was better.

[Cross]

Only one T15E1 gun (with extra long single piece round) was produced, and that gun saw combat. But if there was only one, it may be tough to get data for that gun.

I read somewhere that Hunnicutt's penetration was for the T15E2 gun; post #3 says the T15E1 gun! I don't know which is correct. 25 of the T15E2 were apparently produced, and they had two piece ammo.

You would expect the extra fps over the L53 to give better penetration, unless there was something inferior about the two part shells for the T15E2.

The numbers are so close between the L53 and L73 that it could be that someone mistakenly published the L53 data as L73 and the mistake was then copied in other places.

Perhaps source 3 was the only correct data, and they forgot to mention it was at 30deg?

Keep digging and you may figure it out.

I'll see if can find a good source if I get time.


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[Imp]

Originally Posted by sturmovik

Hmmm, that's odd. The propaganda clearly states that it was better.

Perhaps not so odd the key word being propaganda
Nothing like a morale booster for the troops we have a whizz bang super piece of kit for you guys.
USA tank guns suffered from constant meddling by the arty arm nearly resulting in guns that are designed with there requirements in mind. Normally that's simplicity reliability & a good barrel life but with the net result of poor penetration performance.