

I've always heard it called a Burp gun.
Ok, here's the quick way to make one that's close to it.
First off, you need a German Beretta MG and one of the Gas mask containers from off of the sack that comes with almost any 21st C German soldier.
First step is to cut the clip off of the MG, then cut about 3/16" off of the opening end of the gas mask container.
Next you need to file a slot on the bottom side of the MG right where the clip was. Carefully make the depth to the bottom of the gun barrel.
After this make sure it is square and sand or file the piece of the gas mask container on the end you cut until it is a tight fit into the slot.
Before you glue the magazine drum you made into the gun, be sure the bump of the former catch is on the left side of the gun next to the barrel as you look down the barrel from the stock end. This picture is taken looking down from the barrel end.
Also, the cut end of the drum(that you sanded/filed down) will face the shooter's shoulder. Make sure the drum looks square and straight, then glue in with a drop of CA adhesive.
After the CA dries, I colored the drum black with a fine point Sharpie pen.
And that does it, you now have Russian "Burp" sub MG

Enjoy
