The M&P10 employs a mid-length gas system with a 2-slot, railed gas block (with folding sling loop) that aligns perfectly—both vertically and horizontally—with the numbered, 16-slot, Picatinny top rail machined into the upper receiver. The handguard is a mid-length, 2-piece polymer affair, vented top and bottom, but without internal aluminum heat shields. No open sights are provided.
Upper-to-lower receiver fit is as good as it gets, with absolutely zero play or wobble—a very unusual quality in a production gun. Upon separating the upper and lower receivers we discovered that some genius at Smith & Wesson figured out a quick and simple method for achieving rock-solid receiver fit without the need for costly hand fitting. Small holes drilled in the four corners of the upper receiver’s lower bearing surface—two in front and two in back—hold tiny elastomer pins that act like shock absorbers, compressing and tensioning the receiver halves when joined and eliminating any movement. What a great idea!
Both receiver halves are machined from 7075 T6 Aluminum, with a black, Type III hard-anodized finish. The upper features a Mil-Spec dust cover and forward assist, and a bolt group machined from 9310 steel with hard-chrome-plated carrier bore, gas-key bore and firing pin. The lower is fitted with a Mil-Spec pistol grip and 6-position collapsible buttstock with sling loop, but sports some otherwise novel features: fully ambidextrous controls—safety selector, magazine release and bolt release—that can be operated from either side, and a trigger guard that is integrally machined as a part of receiver.
Overall length is 40.9” with the buttstock full extended, and 37.6” fully collapsed. Empty weight is 7.7 lbs. The M&P10 is fitted with a Mil-Spec, single-stage trigger that, while better than most, still exhibited about 1/8” of take-up and a wee bit of stacking before the break. Average pull weight measured 6 lbs. 3 oz. on our Lyman digital trigger-pull gauge.
For testing we mounted a Trijicon AccuPoint 1-4x24mm rifle scope with German No. 4 fiber-optic/tritium illuminated reticle ($1,050) in a LaRue Tactical LT104 quick-detach mount ($210).
(NOT ACTUAL TESTING RESULTS: Rapid-fire testing at 25 yards on our Salute Products steel-plate targets was completely uneventful—as we have come to expect from Rock River Arms ARs—with no failures of any kind. Rock River guarantees 3/4-MOA precision (3/4 inch groups at 100 yards), but we were able to better that performance considerably during accuracy testing at 100 yards. Our best 5-shot group—measuring an impressive 0.55 inches center to center—was obtained with 60-grain Hornady TAP FPD. Right behind it came Hornady’s TAP FPD 55-grain loading, at 0.60 inches center to center.)
See the M&P10 at your firearms retailer, or for more information contact Smith & Wesson, Dept. OT; Tel.: (800) 331-0852; Web: www.smith-wesson.com
