New Primary Weapon Systems Extended Rail for FN SCAR

Primary Weapon Systems has developed a new quad rail extension for the FN SCAR, the PWS SRX (SCAR Rail Extension). This rail tackles one of the SCAR’s literal shortcomings.

The FN SCAR is a lightweight piston-driven rifle that’s quickly finding its way into the hearts of shooters everywhere, including the military, with the FNAC variant, which is currently one of the candidates to possibly replace the M4 as part of the Army’s ongoing Individual Carbine competition.


One matter of preference with the SCAR is the small package it makes for. Owners of AR-15-type rifles have the luxury of all types of handguard rail systems—the SCAR, with its integrated rails, doesn’t lend itself to many options—and the standard front handguard doesn’t have a lot of room for both hands and accessories.

The Primary Weapon Systems quad rail seeks to fix this by extending the front handguard by an additional five inches, without obscuring the adjustable gas regulator or interfering with sights, optics and other accessories. It doesn’t require the removal of the SCAR’s forward sling points and adds additional limited-rotation quick-detach sling points on either side to boot.


Adding extra rail surface is just one advantage of the SCAR Rail Extension. The SCAR has a reciprocating bolt handle on the left side, which can present problems for thumbs that get too close. The SRX allows you to shoot with your support hand forward far clear of the bolt handle. Here are the specifications:

  • Rails: MIL-STD 1913 Picatinny
  • Length: 5 inches
  • Width: 2.25 inches
  • Height: 2.5 inches
  • Weight: 7.9 ounces
  • Compatibility: SCAR 16S, 17S, L and H

The SRX is mounted to an extended, replacement barrel yoke and doesn’t interfere with the SCAR’s quick-change barrel system. Once installed, field stripping the rifle remains the same. Install is mostly drop-in, and definitely isn’t going anywhere once you get it on there.

Priced at $200, the SRX isn’t outrageous and for owners of SCAR rifles, shouldn’t be too bad at all. If you’re looking to add five extra inches to your rifle, check out the SRX page over at Primary Weapon Systems.

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