YANKEE HILL MACHINE COMPANY SIDEWINDER PISTON 9MM 1/2X28

Description

The Yankee Hill Machine Company Sidewinder Piston 9MM is a suppressor piston for 9MM, threaded 1/2X28.

A piston is the moving part of a booster, sometimes called a Nielsen device. On a recoil-operated pistol the barrel has to tilt and travel a short distance to unlock and cycle the action, and the mass of a suppressor hanging off the muzzle stops that happening. The piston lets the can stay put for an instant while the barrel moves, so the pistol cycles.

Fixed-barrel firearms – most rifles, and blowback pistols and carbines – do not need a booster and use a fixed spacer in place of the piston.

This part is threaded 1/2X28, which is the usual thread on .22 and 5.56 barrels. Thread pitch has to match exactly – a near miss either will not start or will cross-thread, and a damaged barrel thread is a gunsmithing job.

Pistons are specific to the booster assembly they sit in, so it has to be the piston made for your suppressor as well as the right thread for your barrel.

This is a part, not a regulated item. Mounts, pistons, caps and muzzle devices are not NFA-controlled and ship directly to your address – the suppressor itself is the registered item.