SPECIFICATION Parameter D-44 SD-44 Gun weight, kg 1703 2250 Crew, men 6 6 Elevation -7° +35° -7° +35° Traversing ±54° ±54° Bore length, cal 55 55 Rate of fire, shots/min 12-15 12-15 Max. speed, km/h n/a 25 Transportation speed, km/h 55 60 ARMOR PENETRATION TABLE Round Muzzle vel., m/s Angle Distance, m 100 500 1000 1500 2000 BR-367 (AP) 1000 60° -- 110 100 90 80 90° -- 135 120 110 100 BR-365 (AP) 60° 97 90 85 75 70 90° 119 110 100 95 85 BR-365K (AP) 60° 95 90 75 65 55 90° 117 110 95 80 65 BR-367P (APS) 1380 60° -- 155 130 105 -- 90° -- 210 180 150 -- BR-365P (APS) 60° 147 100 80 60 -- 90° 180 140 110 85 --

This gun didn't participate the Second War World, but it was developed in wartime, that's why I decided to examine it here.

The whole D-44 was developed by design bureau of factory #9 ("Uralmash"), but first prototype was manufactured by factory #92 and received ZIS-D-44. After factory's trials gun was slightly improved by factory #9. In May 8, 1945, that improved gun was sent to Gorokhovetsky proving ground, where in May 10, it started its governmental trials. The results see in table. Gun passed a 1512-km race, on roads being carried by "Studebakker" truck (1030 km), off road being carried by "Ya-12" tractor (482 km). See the table below.

According to Governmental commission ZIS-D-44 gun didn't pass the trials because of some reasons, unsuccessful extraction of cartridges in particular. After improving all revealed defects, gun has passed the trials again and was accepted for service under the name "85 mm D-44 divisional gun" Gun had powerful double-buffed muzzle brake; semi-automatic vertical lock (automatic extraction of cartridges); hydraulic recoil brake; cast gun-cradle. Elevation mechanism had one sector. Aiming system consisted of S-71-7 panoramic sight and either OP1-7 or OP2-7 or OP4-7 or OP4M-7 telescopic sight. Additionally, either APN-2 or APN3-7 night vision sight could be used. Gun-carriage had torsion suspension, wheels taken from GAZ-AA truck but were strengthened by GK tyres.

By the end 1948, the self-propelled variant of D-44 was developed. It's ballistic ammo and thus its penetration capabilities were equal to D-44. In November 11, 1954, it was accepted for service under the name SD-44. Totally 697 SD-44 guns have been produced.

In 1947, design bureau of factory #9 has developed new 85 mm ZIS-D-44A divisional gun of a special power. Gun was tested but didn't accept for service.