Rearden SPB 5.56 Muzzle Brake - Plan B - 1/2x28 - Square Shoulder - .280 Bore - Nitride

The Rearden SPB Single Port Brake is a recoil-reduction muzzle brake with a built-in Plan B suppressor mount, engineered to minimize muzzle rise and felt recoil while giving you a quick-detach mounting point.

Features:

• Single-port brake design engineered to minimize muzzle rise and felt recoil
• Threaded 1/2x28 for direct installation onto a matching barrel
• .280-inch bore, larger than a standard .224 5.56 bore, clears chamberings up to 6.5mm
• Square-shoulder design for barrels with a traditional 90-degree shoulder
• Black nitride finish for surface hardness and corrosion resistance
• Precision-machined for a repeatable Plan B taper fit
• Plan B taper mount, also compatible with Rearden Atlas and Atlas XL adapters

This square-shoulder version is meant for barrels with a flat shoulder behind the threads, so make sure it seats flat and square against the shoulder before you torque it down, and keep the threads and tapers clean.

Rearden's Plan B instructions call for cleaning all surfaces, using an alignment rod whenever a suppressor goes on a Plan B-type taper mount, and torquing the muzzle device to roughly 15 to 25 ft-lbs with a thread locker such as Rocksett, then the suppressor to about 10 ft-lbs. Nitride gives a tighter seal, so proper torque matters. Check your suppressor maker's warranty terms before pairing.

Rearden builds Plan B muzzle devices as the mounting point for Plan B-compatible adapters. With a Rearden Atlas adapter (sold separately), they fit most suppressors that use a 1.375x24 rear thread.