range of from their fragmentation shells that were fired at a muzzle velocity of . They had a maximum elevation of +90° and a rate of fire of 160–180 rounds per minute. While being repaired in September 1941, a twin-gun 39-K mount for 55-caliber 34-K AA guns was added. The 34-K guns could elevate between -5° and +85° and had a rate of fire of 15–20 rounds per minute. Their muzzle velocity of gave their high-explosive shells a maximum horizontal range of and an effective ceiling of .