Daniel Defense GL/SSC SBR (12.5")

GL/SSC stands for Grenade Launcher / Sound Suppressor Capable, and the rail is the reason this rifle exists. Developed under SOPMOD Block II, the GL/SSC RIS II is a shortened free-float quad rail sized to a 12.5-inch barrel that carries the M203 mounting hardware in the rail itself rather than in a bolt-on hanger kit. Daniel Defense built only a small original run, most of which went to military users, which is what made the handguard a clone-build white whale before the 2026 commercial release.

The rifle underneath the rail is standard Daniel Defense practice: a 12.5-inch cold hammer forged, chrome-lined, mil-spec heavy phosphate coated government-profile barrel with a 1:7 twist on a carbine-length gas system, wearing a DD A2 flash hider on 1/2x28 threads. The 12.5-inch length is the compromise the program wanted, keeping meaningful velocity over a 10.3-inch MK18 while staying short enough to work in and around vehicles.

This is the SBR configuration, so it is an NFA-regulated firearm: it transfers on an approved Form 4 through an SOT or FFL, with the NFA registration that implies, and federal law sets a minimum purchase age of 21 for a short-barreled rifle. The federal transfer tax has been $0 since 2026-01-01 under the OBBBA; the registration and the approval wait remain. Buyers who do not want the paperwork should look at the GL/SSC pistol, which shares the barrel, rail, and muzzle hardware.