Latest real world weapon lesson from The Firearm Blog TV that features the RPD light machine gun which also has an airsoft version... "The RPD was the culmination of Soviet light machine gun designs that began with the DP-28 of pre-World War Two days, and ending with the RPD, or Ruchnoy Pulemyot Degtyaryova. It was a lightweight, belt-fed from a drum, gas operated machine gun chambered in the Soviet M43 7.62x39mm cartridge. Some call it one of the first true squad automatic weapons, being introduced at least a decade before the Minimi ever came on the scene. It was produced by the Soviet Union, Poland, Egypt, China, and North Korea under various designations. In China it has been asserted that it might have been part of a covert export line of light machine guns, being marked without Chinese markings and with the designation 'M23'.

One of the criticisms of the RPD was the fact that it didn’t have a quick-change barrel as many later light and general purpose machine guns would incorporate into their designs. This forces the user to be somewhat conservative with their rate of fire out of fear of making the machine gun too hot to operate reliably. As we found out in the episode, shooting the entire drum at the cyclic rate of fire makes even the wooden handguards too warm to touch with bare hands."