Tuesday 18 March 2014

17-pounder Trials

As a part of Lend-Lease, the USSR received two British 17-pounder anti-tank guns in April of 1944, which were trialled at the GANIOP between September 8th and November 10th of that year.

17-pounder on trials.

17-pounder on trials, pulled by a Studebaker US6 truck.

#9. The left trail of the gun mount is deformed.

An unfortunate event happened during the test firing: the left trail of the gun mount was dented. The dent later cracked and resulted in the trail bending. It was replaced with one from the second gun. 

Some conclusions:
"The effort on aiming mechanisms is acceptable and ranges from 0.5-4 kg.
The time to go from march to firing position and back is equal to 40-60 seconds.

The gun has a series of drawbacks:
  1. It is not possible to push the gun 500 meters by hand over rough terrain. The 7 man crew can only push the gun 100 meters on flat terrain. Pushing the gun is further complicated by a lack of convenient rails.
  2. The gun is equipped with three different pumps: Studebaker pump for pumping air into the tires, pump for pumping fluid into the recoil mechanisms (of the GAZ-AA type), and two-stage air pump for pumping air into the return mechanism. This complicates use.
  3. The handles of the aiming mechanisms and firing mechanisms are metallic. This leads to freezing hands.
  4. The force required to fire is very high (up to 20-30 kg). The effort to open the breech is too high (up to 15-20 kg).
  5. The recoil indicator is poorly placed behind the gun shield, leading to complications when controlling the recoil length.
  6. Adding fluid to the recoil mechanism is difficult, as it requires the crew to leave the protection of the gun shield.
  7. Observation of the results of the shot is difficult due to the smoke and dust kicked up by the muzzle brake.
  8. The firing mechanism is unsatisfactory. Due to firing handles getting stuck on each other when the gun returns after firing, the gun cannot fire without fault.
  1. Advantages of the English 17-pounder anti-tank gun:
    1. High penetrating power.
    2. Fault-free operation of the recoil mechanisms and breech.
    3. Good precision and stability.
    4. Easy to read recoil and return gear mechanism fluid levels.
  2. Drawbacks of the English 17-pounder anti-tank gun:
    1. High combat weight (2860 kg).
    2. Small coefficient of metal use (112).
    3. Insufficient robustness of the trails.
    4. Additionally, drawbacks stated in section 3 part 10.
  3. Compared to our anti-tank guns, the English 17-pounder anti-tank gun is heavy to move between positions and inconvenient to transport.
  4. Three different pumps makes the system difficult to service.
  5. The report on trials of the English 17-pounder anti-tank gun was composed carelessly, and the report on trials of the pumps, due to an absence of one of the pumps, is inaccurate due to unfamiliarity with what each of the pumps does and the principles of filling the return mechanism with fluid or air.
Conclusions of the Artkom 2nd Department:
  1. The penetrative power, stability, and precision of the English 17-pounder anti-tank gun makes it a powerful anti-tank gun that meets modern requirements for anti-tank artillery.
    However, the gun is very heavy for its caliber (2862 kg), has a low use of metal coefficient (112) and many other drawbacks, listed in section 3.
  2. The gun has the following original components:
    1. Separable box trails with variable cut, that curve upwards in the middle and are reinforced internally by riveted trusses.
    2. The firing mechanism has three levers. The lever for firing by the breech operator is located above the breech on the gun mount case and works by pulling.
      Two levers are located by the gunner. One is mushroom-shaped in the center of the turning mechanism, and one is a lever located under the turning mechanism. The two latter levers transfer the gunner's force to the first lever.
    3. During storage, in order to avoid corrosion, the recoil mechanisms are not filled with fluid. The barrel is held in place by a special holder.
    4. The optical telescopic sight and vision device.
    5. Spaced armour gun shield. The thickness of one armour plate is 6 mm.
    6. Floating piston for separating air and fluid in the recoil brake.
    7. Recoil and return length regulator.
  3. The presence of three pumps in the system complicates service.
  4. Remove the "top secret" classification from the short description received from GIARP and replace it with "for service use".
  5. Send one copy each of the short description to the Chair of the Council of People's Commissars Technical Council, Chief of the Dzerzhinkskiy Artillery Academy, and the 15th Department of Artkom.
  6. Print the conclusions and send to the addresses in the original.
Chief of the 2nd Artkom department, Major-General of the Artillery Service, Komarov
Deputy Chief of the 2nd Artkom department, Engineer-Colonel Tihomirov
Senior Engineer, Artkom 2nd department, Engineer-Major Kornienko"


  1. What is the use of metal coefficient?

    1. The ratio of the final device to metal used. In this case it doesn't make sense, since it's supposed to be between 0 and 1, but that's what was in the original.

    2. I believe it's some sort of power-to-weight ratio. Muzzle energy divided by gun weight (or something like that)

  2. When would it have been of any use for the russian army? By that date, wasn't the BS-3 already deployed?

    The Zis2/3 and 45mm M42 were enough most of the time anyway, except front of panther/tigers.

    A good gun in WW2 would have been the D-48 of 85mm, too bad it was not made in 1944.

    I think the best ATG was the PaK40, almost no contest. Low profile, quite mobile, and good power. The Zis-3 was totally inferior in AT role (it wasn't its primary role though) The ZIs-2 was certainly powerful, but, it penetrated less IIRC (not able to penetrate tiger 1 on front ? past 500m?)

    the 6pdr (or US 57mm M1 variant) was also a very good gun, for its size. How many of those were exported to russia ? What the soviets thought of it ?

    Imho, top ATG or WW2 : PAK40, 6pdr, Pak38, Zis-2, 17pdr.

    1. The BS-3 is some 800kg heavier, its round is still significantly larger and heavier plus it doesn't have advanced ammunition in war (not even APCR!)

    2. 17pdr ATG would be of no use to soviet units.
      It´s a high velocity gun and in order to be effective at high impact velocities, the APCBC projectiles required an armour piercing cap, a steel body composed of high alloy content to allow the full utilization of hardenability without loss of toughness.
      Soviet uncapped AP were too soft in ww2 and generally are of limited benefit in high velocity guns (improving only the downrange penetration but not the maximum or short range penetration due to projectile break up).

  3. ZiS-2 penetrated practically same as PaK40, was lighter and had pneumatic tires (important for preventing loosing boresight during motorized transport, which was a problem with PaK40). 6pdr was also close in performances with less weight.

    Best - ZiS-2, 6pdr and PaK40 share 1st place, PaK had decent HE shell also so would be also used to support infantry while 6pdr/ZiS-2 were more specialized. Others were too heavy to be really good or too low penetration to matter.

    1. I didn't know about those advantages for Zis2.

      The Pak38 was a great gun, but hopelessly obsolete by late in the war. Its problem was not that it was bad, but that it was late by 2 years... Had it been the main ATG of 1939-1941 campains (as its name would suggest, "pak38"), it would have been amazing. I still consider it a great gun, for facing anything before T-34, KV-1 and sherman.

      The 17pdr was surely best heavy ATG of the war. The PAK-43 was horrendously immobile. 17 pdr had sufficient penetration for WW2.

    2. Zis-2 doesn´t penetrate as much as PaK 40 with their respective ww2 service ammunition.
      Zis-2 failed to perforate 100mm german RHA frontal armour of TIGER-1. 75mm PaK-40 with PzGr. 39 does penetrate 132mm vertical german RHA plate at the reduced muzzle velocity (750m/s instead of 792m/s for new gun) in five out of five cases and is probable to penetrate Tiger 1 front / sides out to ranges in excess of 0.9km and 1.5km, respectively.