Luth-AR GB-750A Adjustable Gas Block .750" - AR-15/AR-10

The Luth-AR GB-750A Adjustable Gas Block is a low-profile, set-screw adjustable gas block designed for AR-15 and AR-10 pattern rifles chambered in 5.56/.223 and 7.62/.308. It fits standard barrels with a .750" gas block journal diameter and installs as a direct replacement for a factory fixed gas block or as an upgrade on a new build.

Machined from heat-treated 4140 steel and finished in a corrosion-resistant black coating, the GB-750A keeps a slim, low-profile footprint that tucks neatly under free-float handguards. The set-screw adjustment lets the shooter tune gas flow to the operating system, with + and - indicator markings engraved around the adjustment screw for quick at-a-glance reference.

At just 1.0365" overall length and 1.33" tall, the GB-750A drops cleanly into most drop-in handguards and free-float rails. Inside diameter is .750" with an outside width of .9365", secured to the barrel by two 1/4-20 x 3/16" set screws for a positive lock-up.

Whether you are building a new rifle or replacing an existing fixed gas block, the Luth-AR GB-750A is a straightforward, durable upgrade for the AR-15 or AR-10 platform.