25 mm is caliber of 72-K - one of most used soviet AA gun in WW2. Degtyarev worked in 1929-1933 at 25 mm autocannons, with new cartridge:
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Also, created high-velocity LPP-25 AT gun, and two (or more) recoiless cannons.
I haven't data about early Soviet 25 mm cartridges.
Project of SB with 25 mm ADZP gun (Automatic double-bolt cannon) - very weird weapon, two barrels, and crazy loading system - special box-cassets (Rus. "короб-кассета"), with pushing out to horizontal conveyor, where cartridges take by revolving cilinders and load to barrels. System work on electric motor. Box-cassets were under and over the conveyor. Used cases taked to backside of bomb bay.
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Also, worked at montage of five ShVAK 20 mm cannons:
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