Depending on who you talk to, the Bren gun is either the best light machine gun of WW2, or it's the best light machine gun of WW2.  Adopted and modified by Britain from a Czech design, even the name, Bren, is short for Brno, the city where the gun was designed, and Enfield, of the Royal Small Arms Factory.  Brits and the Commonwealth countries liked them so much they used them until after the 1st Gulf War.  That says a lot for old world design, it may be heavy and overbuilt, but you can depend on it and you are unlikely to wear it out.

Bren gunner

Our favorite guys over at Forgotton Weapons did this very informative video, after which you could probably field strip the gun yourself with your eyes closed.  And of course they have to shoot it...