Jason Clower’s video on the development and use of the Type 85:
The Type 85 was a submachine gun developed in the 1980s in China to replace the failure that was the Type 79. It was a very simple design; firing from an open bolt and using a plain blowback action chambered for 7.62x25mm Tokarev. Two different models were made, one regular and one with an integral suppressor.
Type 79 SMG: https://youtu.be/dWIbsLxqBPc
Kokalis did a write up on this and the earlier type 64 back in his SOF days.