what is the difference between m1 and m2 carbine?
The M2 carbine is the selective-fire version of the M1 carbine capable of firing in both semi-automatic and full-automatic. The M3 carbine was an M2 carbine with an active infrared scope system. Despite having a similar name and appearance, the M1 carbine is not a carbine version of the M1 Garand rifle.