This gun designer served time in prison for second degree murder.
John Garand
David Williams
John Browning
Hiram Maxim
David Williams, also known as "Carbine" Williams, designed the short-stroke piston used in the M1 Carbine, as well as the floating chamber operating system. Williams was convicted of second degree murder after a deputy was shot and killed during a raid on Williams’ illegal still in 1921.