Precision Armament AccuWasher Gen 2 Muzzle Device Alignment System – Shim Kit

AccuWasher Gen 2 Muzzle Device Alignment System

The AccuWasher Gen 2 kit from Precision Armament replaces crush washers, peel washers and stacked shim packs with a single precision-machined mono-shim. Each shim in the kit is a different thickness, so you simply pick the one that brings your muzzle brake, flash hider or suppressor mount to the correct index when torqued. The result is exact timing that stays put, without the guesswork or the deformation that a crush washer introduces.

Because the shim is a single solid piece with certified circular thickness uniformity of .0001″, the muzzle device sits perfectly square to the bore. That matters for accuracy on any rifle and is essential for suppressor use, where misalignment can cause a baffle strike.

Why a mono-shim instead of a crush washer

• Exact timing: select the shim that indexes the device correctly at full torque, then reinstall it identically every time.
• No shear-slip or yielding: the monolithic construction and substantial thickness mean nothing compresses, rotates or works loose under fire.
• Strength: made from high-strength steel, equal to or stronger than barrel steel.
• Accuracy and safety: eliminates the alignment errors that stacked shims and crush washers cause, giving the highest insurance against a misaligned suppressor or brake.
• Fast, intuitive installation: external markings identify each thickness, so the correct shim is found in seconds.
• Shoulder clearance: chamfered on one side to clear barrels with radiused thread shoulders.

How it works

Thread the muzzle device on without a washer and note how far short of the index it stops at hand-tight. Choose the shim whose thickness closes that gap, fit it against the barrel shoulder, and torque the device to specification. If the timing is slightly off, step one shim thinner or thicker. Once set, the same shim gives the same result on every reinstallation, which makes cleaning and device swaps painless.

Kit options

Each kit is matched to one barrel thread and one shim outside diameter. The 1/2×28 kit uses .725″ shims, the 5/8×24 and M15x1 kits use .825″ shims, and the 3/4×24 and M18x1 kits use .925″ shims. Larger-diameter kits for bull barrels are available separately, and the AccuWasher Gen 2 Shim Adapters let a larger shim be used on a smaller thread for a seamless look.

Specifications