The Troy .875 Low Profile Gas Block (brand part no. SGAS-875-00BT-00) is purpose-built for AR-pattern bull barrels that use a 0.875-inch gas block seat, a size that does not fit most standard-contour barrels. Troy machines it from 4140 pre-hardened steel and finishes it with a MIL-STD manganese phosphate coating for corrosion resistance that matches mil-spec parts elsewhere on the rifle. Its low-profile design tucks under most free-float handguards without adding bulk to the barrel’s forward end. Shooters should have a gas tube roll pin on hand, since it is not included with the block.

Key Specifications

• Sized for a 0.875-inch gas block seat, matching bull-barrel contours rather than standard AR profiles.
• Low-profile design fits under most free-float handguards without added bulk.
• Machined from 4140 pre-hardened steel for durability under sustained fire.
• Finished with MIL-STD manganese phosphate coating for corrosion resistance.
• Ships without a gas tube roll pin, so have one on hand before installation.

Frequently Asked Questions

Does this gas block fit a standard-contour barrel? No, it is sized for a 0.875-inch gas block seat found on bull-barrel rifles, not standard AR contours.

Is a gas tube roll pin included? No, the roll pin is not included, so have one on hand for installation.

Buy the Troy .875 Low Profile Gas Block

If your bull-barrel build needs a gas block that actually fits its 0.875-inch seat, this low-profile Troy block gets the job done without crowding your handguard. Browse more AR gas system parts from Troy Industries and order it from our Lubbock, Texas gun shop for fast, insured shipping.