Ing pungkasan abad kaping 19, akeh desain anyar kayata M1895 Colt <unk> Browning lan Hotchkiss dikembangake, didhukung dening operasi gas utawa operasi recoil. Uga, tinimbang jaket banyu abot, desain anyar ngenalake jinis pendinginan barel liyane, kayata penggantian barel, sirip logam, sink panas utawa sawetara kombinasi kasebut. Pitakon: Apa macem-macem jinis pendinginan barel?
panggantos tong, sirip logam, sink panas