The Mauser C96 aka 1896 aka "Broomhandle" was the first successful automatic loading pistol. Between 1896 and 1939 it enjoyed many upgrades including being chambered in 7.63mm (the highest velocity round available until the .357 magnum), 9mm, and .45 cal. There were full automatic machine pistol versions, various barrel lengths, and holster styles.
An experimental aircraft machine gun made from linked Broomhandles.
Brazilian full auto Broomhandles.