Here's a review of the Colt 6720; a very under rated rifle in my opinion.
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Music by Youtube Creators & Machinima Sound
Brownells Dream Gun Completion
How Powerful are Short Barrel AR-15s?
Okay Industries Surefeed AR15 Magazine Review
Wheaton Arms Comp Review & Full Auto Field Test
AR15 AR-15 ammo test: Lehigh Defense Controlled Chaos .223