Centurion Arms SR-25 MK11 Mod 0 Quad Rail, 12.5″ Rifle Length The SR-25 MK11 Mod 0 Quad Rail from Centurion Arms is a modest reproduction of the Free Float RAS from Knight’s Armament Company. The original KAC SR-25 Free Float RAS (Rail Adapter System) was originally designed for the US military’s Mk11 Mod 0 rifles. Much like the original, the Centurion Arms MK11 Quad Rail features full length mil-spec M1913 Picatinny rails at the 12-, 3-, 6-, and 9 o’clock positions, making it compatible with any number of rail-mounted tactical accessories. The rail free floats the barrel, allowing for consistent barrel harmonics upon firing, and thus increased accuracy potential. It is recommended that this MK11 Quad Rail be used with a rifle length gas system only due to potential interference issues if a gas block were to be run underneath the rail. The top rail has a cut-out in it that is meant to be a recess for a folded KAC Mk11 Push Button Front Sight (PN: KM20138, sold separately). Disassembly of the rifle’s gas system and removal of the factory barrel nut will be necessary. This forend uses a proprietary barrel nut that must be installed using a SR-25 RAS barrel nut wrench (sold separately). Specifications Free Float: Yes Material: Aluminum Finish: Black Anodizing Click here to browse our entire selection of Handguards.
