Similar to MR556A1, except 7.62x51mm chambering, 10- or 20-shot magazine, upper and lower accessory rails. Also made in LRP (Long Rifle Package), with Leupold 3-9x40mm VXR Patrol scope, LaRue Tactical BRM-6 bipod, collapsible stock with adjustable cheekpiece. NOTE: Add $2500 for LRP model.