by Shooting Illustrated Staff posted on October 21, 2010 Guns Support NRA Shooting Illustrated DONATE Benelli MR1 In this article 5.56x45 mm, Benneli, semi-auto rifles Related Stories DPMS Panther 3G1 Gallery DPMS Sportical Gallery The Truth About Pistons Barrett REC7 Chambered in 5.56 NATO Gallery Auto-Ordnance AOM160 M1 CarbineAuto-Ordnance AOM160 M1 Carbine Gallery Most Popular How To Begin Loading Your Own Ammo Five Great 1911s for Concealed Carry 10 Budget-Priced .22 Rifles Under $200 Top 5 'Budget-Priced' .50 BMG Rifles 9mm Double Stack 1911 Pistol Roundup Let’s Talk About Human Predators