Footnotes

1. M–30S and M–30 obr.1938. Source: Russian Military Zone and Red Steel. New ammunition BP–460A was introduced in May 1943. Red Steel refers to a HEAT projectile being developed, “…but was only accurate at short ranges and its penetration was still disappointing”. The projectile weight and muzzle velocity have a question mark “?” indicating these are for an unknown projectile (i.e., not necessarily the BP–460A). [up]

2. D–25S, D–25T, D–2, S–4 and A–19 obr.1931/37. Source: Russian Military Zone and Red Steel. The D–25S and T was an A–19 with better designed breech block and a higher, but still slow, rate of fire (4 rounds per minute instead of 2 rounds per minute). The D–2 and S–4 are mentioned in Soviet Guns 1920–1945 as having identical ballistic characteristics to the A–19. There are minor differences in penetration data (about 2mm) in different sections of the Russian Military Zone, so the figures from the IS–1/IS–2 page are used as they are more complete. The barrel length is L47.9 for the muzzle brake of German design, or L48.5 for the TsAKB designed muzzle brake. [up]