Entire S.I.R.front-end can be installed in less than 5 min. directly to the standard barrel nut without Delta ring. Totally Free Floating. Front sight, gas tube, and front handguard retaining cap do not need to be removed. Barrel does not have to be removed. Standard barrel nut does not need to be removed. Perfect alignment with the receiver can be accomplished via built-in alignment anti-rotation locking tabs. No special tools required. S.I.R. standard sling swivel is useable for installation. The system weighs only 8.6 oz. The weight will increase depending on what selective rails are chosen to be utilized plus the weight of the sling swivel. Hanguards complete with QD indirect airflow heat shield. The S.I.R. selective rails at 3, 6, and 9 o'clock positions can be exchanged, repaired, or replaced without removing the main top rail. Super-cool offset heat venting. The optional S.I.R. rail also provides a modular means to cost-effectively upgrade into future integral electronics, and provide a solid platform, can eliminate the need to use high, less-stable, mounting devices, plus protects the top of the aluminum upper receiver at the same time protecting the receiver; can eliminate replacement of a damaged receiver.
The #50M-CV allows the M203 launcher to be free float attached with no modification whatsoever to the launcher's receiver. The #50M-CV allows the A.R.M.S. dual QD 1913 M203 attachment brackets to install to the S.I.R. upper handguard just like the polymer handguard. The #50M-CV launcher QD attachment brackets provide a built-in 1913 dovetail rail along the length of the handguard at the 3 and 9 o'clock positions, multiple position attachment of grenade launcher sights.
