Tuesday 2 December 2014

Penetration, Part 8: Cold War Edition

Time passes, friends become enemies, enemies become friends, but the need to know what your enemies are capable of doesn't go anywhere. Naturally, as the USSR continued its research into weapons, the United States continued trying to discover information on those weapons. This is what they came up with.

PAM 30-60-1 Vol. 3 Pt. 1 (composite image from several pages)

Lots of good old friends, as well as newcomers, so let's go through this list and see what we can find.

The first gun is the D-56T mounted on the PT-76 amphibious tank. It seems new and exciting, but it's actually just a boring old ZiS-3 in a tank form factor. So boring and old, in fact, that the penetration data comes straight from this table right here, for APHE at least. The APCR data is not recorded in that table (probably because it has less penetration than AP at this range). HEAT is also new, and clearly a different round than was tested with the F-34. That one didn't perform nearly as well.

The next gun is the S-53, mounted on the T-34-85 and T-44. The rate of fire of only 3-4 RPM is rather low (average sustained RPM using all racks according to Soviet data is 6). The penetration for APHE is the same as the Soviet table again, but APCR is new, same as with the D-56T. Unlike the D-56, however, this round is actually more effective than AP at this range, which is probably why it doesn't get HEAT.

Next is the D-10T, from the T-54. Unlike with the predecessor, the rate of fire is straight out of the manual. Here, the penetration for AP is much greater than the old Soviet table (likely owing to post-war ammunition). The HEAT shell for this gun packs quite a punch, way above the dinky old D-56.

Now here's the good stuff, the smoothbore U-5TS from the T-62. The tank was built around the gun, and it shows. New APDS ammunition puts the D-10T to shame, and HEAT penetrated an impressive 450 mm of armour. 

The D-25 is next, installed on every Soviet production heavy tank from the IS-2 to the T-10. Penetration here is a little higher than the Soviet table (160 vs. 147). Otherwise, there really isn't that many new things to be learned about it.

The successor of this gun, on the other hand, is much more interesting. This is the "122 mm T-10 tank gun", or better known to most as the M-62, mounted on the T-10M, but compatible with any D-25 mount. The AP shell of this gun penetrated 185 mm of armour at 1000 meters, which isn't that impressive. The bigger improvement is the HEAT shell, which penetrates a whopping 460 mm.

The next gun is a little more obscure, the 57 mm Ch-51M from the ASU-57 airborne SPG. The values here are lifted straight out of the manual (although APCR penetration at this range is listed as 101 mm in the manual instead of the 100 in the table). Looks like American intelligence was doing its job properly.

The next gun has a fancy title, but this is just the plain old ZiS-3 again. Comparing data with the D-56 will give you some differences in the mount, but otherwise, it's functionally identical.

The D-5S-85 is another gun you should be familiar with, from the Soviet SU-85 SPG. The same gun was mounted on the more modern ASU-85. As expected, its performance is exactly the same as the S-53.

The D-25S is another "double", with all data identical to its tank-based version, but in the end of the list, the ML-20 awaits! However, it doesn't have anything new to tell us. Penetration data is, once again, pulled straight from the Soviet table.


  1. Nice data. As it seems, the m-62 penetrated less than the bl-9.

  2. did they plan to use new 122 mm HEATs to the D25 guns?

    1. Yes, there were HEAT shells developed for the D-25 gun.

    2. No, sadly. I'm going to be doing a lot more research into post-war armour than I initially intended to in the coming months, so keep an eye out.

  3. The D-25 is next, installed on every Soviet production heavy tank from the IS-2 to the T-10. Penetration here is a little higher than the Soviet table (160 vs. 147).

    Most of the table seems to be just Soviet data, and as it's been mentioned before, the Soviet used more stringent criteria of what constituted "penetration" than the West. Did the US do none of its own testing? That seems odd, you'd think that in many cases they'd have some of these weapons captured.

    So why this outlier? Is that figure

    1. Where would the US have gotten a D-25? The British were lucky enough to find one in some rubble in their sector of Berlin, but I don't think the Americans got a chance to grab one. There also weren't any in Korea. I'm sure they could have gotten their hands on an Egyptian IS-3, but by that time the D-25 was obsolete and there was no point in testing it.

    2. There ARE US tests of a a-19 or D-25 on american standarts. The results are in ww2 ballistics armor and gunnery.

    3. That's right. The US did have A-19 to test. And as Thor states they were tested to the US 'protection' criteria of armor penetration. The D-25 could be found by adjusting the velocities differences in MV.

    4. Where would the US have gotten a D-25?

      The Americans grabbed a IS-2 tank turret, off tank 441 of the 7th Guards Heavy Tank brigade, from their sector in Berlin. Plus there's also another IS-2 mantlet and gun on display at the Southern New England Military museum in Danbury CT:


      So. yes, the US had access to captured D-25s. Moreover, insofar as 'obsolete' weaponry, most of the weapons on the table are of WWII vintage, in performance if not in name...the outliers are just two more modern weapons, the U-5TS 115 mm smoothbore from the T-62, plus the M-62 on the T-10.

    5. Huh, interesting, you'd have thought the gun would have been damaged beyond use by an ammunition rack explosion.

  4. Something is weird. Why is the D-56T (designed as a LIGHT WEIGHT canon) listed as being HEAVIER than the 85mm?

    Even the old ZIS-3 with all the mounting, wheels, etc weighted 1116 kg.