90mm ammunition load out changes

Machinery of War Discussion Ground Vehicle
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1

There are quite a few issues with how Gaijin has implemented the short and long 90mm guns. One of which is the ammunition each vehicle is given to use.

The following rounds were developed for the 90mms:

AP:
M77
T33
M318
M318A1
T43
T54 not in game

APC:
M82 with 199 grams filler at 2670 fps not in game
M82 with 140 grams filler at 2670 fps
M82 with 140 grams filler at 2800 fps
M82 with 140 grams filler at 2850 fps (scrapped due to barrel wear) not in game
M82 at 3200 fps (I believe the Super Pershing used M82 instead of T41)
T39 (possibly M82 at 3050 fps) not in game
T41 (M82 with larger driving bands for separately loaded T15 guns)
T50 separately loaded not in game
T50 fixed not in game

APCR:
M304
M332
M332A1
T44

APDS:
T137 not in game but 105mm T279 uses same sub projectile

HEATFS:
M348
M431

HE:
M71
T42

I am suggesting the following load outs for US tanks. If anyone can find documents for foreign operators of these tanks, I will add their load outs too.

Pre 1944 and prototypes:
T25, M4 T26
-M77 and M71 stock
-M82 with 199 gram filler at 2670 fps
-Maybe APCR but designated T30E16

T26E1-1 Super Pershing
No load out changes but correct designations for rounds. T33, M82, M304 and M71.

T32, T32E1
No changes unless T50 is implemented.

M26E1
Change designations to same as Super Pershing

M18 Super Hellcat, T26E5
-T33, M82 with 199 grams filler at 2670 fps, M71 stock
-M82 with 140 grams filler at 2800 fps
-M304

Post 1944 WWII vehicles:
M26, M36
-T33, M82 with 199 grams filler at 2670 fps, M71 stock
-M82 with 140 grams filler at 2800 fps
-M304

Post WWII and Korea:
M46, M46 Tiger, M36B2
-M318, M82 with 199 grams filler at 2670 fps, M71 stock
-M82 with 140 grams filler
-M332
-M348

Post Korea:
M56
-M318, M82 199 gram filler 2670 fps, M71 stock
-M82 140 gram filler 2800 fps
-M332
-M431

M47
-M318A1, M82 140 gram filler 2800 fps, M71 stock
-T39
-M332A1
-M431

M48A1
-M318A1, M82 140 gram filler 2800 fps stock
-T39
-T137

5 Likes
2

I’m curious about the specifications of this AP round. When was it developed? For what cannon?

I’d love to see M82 at ~930 m/s for the M47s and M48s if that actually is a thing. Although even if it existed it probably was just a test round and Gaijin wouldn’t accept it.

I don’t feel like this is correct as the M26E1s were tested post war from 1947 to 1949. By that point the 90 mm T15 cannons existed and I assume so did their ammunition (T41 APC, T42 HE, T43 AP, T44 HVAP and T50 APC rounds). Just doesn’t make much sense in my mind to already have developed rounds specifically for these higher velocity 90 mm and then not use them.

3

The T54 is a modified T33. I’m not sure exactly what was changed but I don’t think it made much difference.

The T39 was real. It was a prototype round and never was adopted but it would help the M47 and M48A1.

The T54 90mm was in development along side the T15. From what I can understand, the T41, T42 and T44 were the M82, M71 and M304 modified for separate loading. The T54 90mm was not separately loaded ammunition. The T50 was adapted to a fixed cartridge loading for the M3 and T54.

4

According to Hunnicutt the T54 was developed after the T26E4s had been equipped with the T15E2 because it was still difficult to load:

After the difficulties with separated ammunition in the T26E4, the 90 mm gun T54 was developed to
provide a weapon with a fixed, one piece round suitable for use inside a tank turret. The ballistic
performance and chamber capacity of the 90 mm gun T15E2 were retained, but the cartridge case was redesigned with shorter and fatter dimensions. This provided a complete round of convenient size to handle and load inside the tank turret. The overall length of the T54 was less than the T15E2, due to its shorter chamber and the muzzle brake was reduced to a single baffle model by machining off the front baffle from a standard 90 mm brake.

Still, if you say that the T41, T42, T43 and T44 rounds were all developed specifically for separate two piece loading with no modifications done to turn them into fixed cartridge then the M26E1 probably would’ve used the normal projectiles like M82, T33, etc, except for T50 as you stated.

5

I’ll add a few more here.
Suggested ammunition for Post Korean war vehicles

  • T33E4 for 90mm Guns M36, M41 and T125, MV 3050. slightly higher velocity than M318 or M318A1 fired at 3000 ft/s, slightly higher penetration.
  • T65 HVAP-DS-T for 90mm Guns M36, M41 and T125, authorized for service. 4,100 ft/s muzzle velocity.
  • T91 HE, developed to replace M71 in 90mm Guns M36, M41 and T125. 3.5 lb TNT or Comp. B filler (4.585 lb. TNTe)

Suggested ammunition for M46 and M36B2.

  • M71 HE with Comp. B filler for 90mm Guns M3 and M3A1. 2.15 lb Comp. B, 2.8165 lb TNTe.
  • T142E3 HEP for 90mm Guns M3 and M3A1.
6

I’m not sure Gaijin will add more prototype rounds. I think the T39 is would be beneficial but I’m not sure an extra 50 fps would be.

I left the HEP round out because it’s not really useful. APHE and HEATFS are more useful.

I don’t know enough about the T65 HVAPDS. The T137 is essentially in the game already, and that may help bring it to the 90mm tanks.

7

It’s been a while since I read into it but I thought the T54 and T15E2 were being developed along side each other.

As for the designations, it’s a minor issue. The M26E1 doesn’t even get them. It says T41, HE, AP, APCR. Odd how Gaijin didn’t change all of the rounds.

8

My question is why the M318A1 is slower than T33E4. Did T33E4 at 3050 ft/s create too much barrel wear?

9

I have no idea regarding that issue. Maybe Conraire can give you an answer.

10

Either way, it works out to 4 or 5mm more pen so I’d rather get T39 over T33E4.

11

One thing I want to add is that I fail to see why the M18 (90) and T26E5 are limited to earlier ammunition, as both of these vehicles are very late war prototypes, as both appeared in June 1945, with more T26E5s being built afterwards.

I can understand why the T25 and M4/T26 fire the weaker rounds but not the M18 (90) or T26E5.

1 Like
12

That’s a good point. I forgot when both those tanks were built. I’ll change it.

13

I copied and submitted this as a suggestion. Just waiting on approval.

2 Likes
14

My suggestion got deleted and I have no idea why.

15

You’re missing some it seems, this is the gun mounted on the T32 tank. (Super Perishing’s is T15E1 which is one piece unlike the two piece of T15E2)
This exert was found by Captain Nemo of the Tank Encyclopaedia team, he also made these neat tables.
I think he has more tables like this of other 90mm guns you’d have to ask him on the TE discord.
image

16

I covered the T32 and T32E1. The only changes needed would be to remove the T41 and add the T50.

17

It would have the exact same performance with the calculator, wouldn’t it?

Unless T50 has 140 grams of filler and T41 specifically has 199 grams.

18

The calculator would give the same result, so it doesn’t really matter.

19

@Smin1080p can you clarify something for me? I was working on a suggestion for these changes to the ammunition available and I have been getting conflicting answers. I was told that each tank would have to be reported individually. The issue is would they be bug reports or suggestions?

20

@MiseryIndex556 I’ve seen your suggestion for the M26 to get two different M82 variants on the Gaijin bug report site, and that it has been acknowledged. Hopefully this lets us get closer to better representation of the ammunition of the 90 mm cannons.