The B&T Alpha piston 1/2×28 is a threaded piston mount for running a suppressor on a semi-automatic pistol (B&T part no. SD-145658). Most centerfire pistols use a short-recoil action, and hanging a suppressor’s weight on the barrel can slow the action enough that the pistol fails to cycle. A piston mount solves that by letting the barrel move at close to its normal weight while the suppressor rides on the piston, so the slide keeps cycling. This one threads onto a 1/2×28 muzzle, the common thread pitch on 9mm pistol barrels. It is a small part, but it is the one that makes a suppressed handgun run.

Key Specifications

• The thread pitch is 1/2×28, the standard pattern on most threaded 9mm pistol barrels.
• It is a piston mount, the part that lets a short-recoil pistol keep cycling with a suppressor attached.
• It is a pistol-specific mount, made for handguns rather than rifles, which use fixed mounts.

Frequently Asked Questions

Is this a suppressor? No. It is a piston mount that connects a suppressor to a 1/2×28 threaded pistol barrel. The suppressor is sold separately.

Why does a suppressed pistol need a piston? A suppressor adds weight to the barrel of a short-recoil pistol, which can keep the action from unlocking and cycling. The piston lets the barrel move freely so the pistol keeps running.

Buy the B&T Alpha Piston, 1/2×28 Thread

If your suppressed pistol short-strokes or fails to lock back, this is the piece that sorts it out. Browse more from B&T alongside our suppressor parts and accessories, and order from our Lubbock, Texas gun shop for fast, direct shipping to your door.