The Degtyarev DP (aka DP-27) was the subject of a bunch of experimentation during the 1930s, but none of the trialed modifications were actually adopted. It was only in 1944, after several years of combat experience, that the design was updated to correct a number of shortcomings. Specifically:

- The recoil spring was moved away from the gas piston and up behind the bolt to prevent its overheating.
- The traditional stock and grip safety were replaced by a pistol grip and manual safety.
- The detachable bipod was replaced by a more permanently attached model.

The DPM was a much better-handling gun than the original DP, and it maintained the simple disassembly and economical manufacturing of the original. The pan magazines remained a complaint because of their awkward handling, but no easy change was available for that during the war.