Bear Creek Arsenal BC-15 5.56 NATO 7.5" 30rd M-LOK Pistol

At 7.5" this is about as short as a 5.56 AR gets before the gas system runs out of room. Bear Creek pairs the stubby chrome moly barrel with a pistol length gas system, which is what makes a barrel this short cycle reliably in the first place. The barrel wears a parkerized finish, and the whole gun ends up small enough to live in a bag or behind a seat where a carbine simply will not fit.

Understand what a 7.5" 5.56 is and is not. Muzzle blast is loud and the flash is bright, and a good chunk of the powder finishes burning outside the barrel. In exchange you get a rifle caliber gun with the footprint of a large handgun, which is exactly the trade some people want for close quarters work. The M-LOK handguard free floats the barrel with slots for a light and a hand stop, an adjustable buffer tube comes fitted with no brace, and one 30rd magazine is in the box. AR-15 pattern parts drop in throughout, so a different trigger, grip, or charging handle is a five minute job.