Precision Armament’s AccuWashers
Precision Armament’s AccuWasher system is a specialized muzzle device alignment solution designed to replace traditional crush washers and stacked shims with a far more precise and controlled method of indexing. At its core, the system uses a single, precision-machined washer rather than multiple stacked components, which eliminates tolerance stacking and significantly improves alignment consistency. This design allows shooters and gunsmiths to achieve exact timing of muzzle brakes, compensators, and suppressor mounts without the guesswork typically associated with older methods.
One of the most defining characteristics of AccuWashers is their extremely tight dimensional tolerances. Each washer is lathe-machined on both faces and held to a thickness uniformity of approximately ±0.0001 inches, which is far tighter than conventional shims. This precision ensures that the muzzle device aligns correctly with the bore axis, reducing the risk of accuracy issues or serious alignment problems when using suppressors. The system typically includes a set of 18 individually marked washers of varying thicknesses, allowing for timing adjustments across a full 360 degrees in roughly 20-degree increments.
In terms of dimensions, AccuWashers are produced in several standardized sizes to match common barrel thread patterns. For example, the Gen 2 system includes outer diameters of approximately 0.725 inches for 1/2-inch threads, 0.825 inches for 5/8-inch threads, and 0.925 inches for 3/4-inch threads. Thickness ranges vary depending on the size, typically spanning from about 0.040 inches to 0.108 inches, which provides enough variation to fine-tune alignment without stacking multiple components. Earlier versions had slightly larger outer diameters, such as 0.750 inches for 1/2-inch models, but newer designs prioritize a more refined fit and improved compatibility with modern barrel profiles.
Versatility is another major strength of the AccuWasher system. While older shim kits were often limited to a narrow range of thread sizes, newer iterations incorporate adapter components that expand compatibility across nearly all common thread pitches and barrel configurations, including some metric options. This makes the system suitable for a wide range of firearms, from lightweight carbines to heavy precision rifles. The ability to use a single washer for each installation, combined with clearly marked thickness values, simplifies the process and allows for repeatable, predictable results even across multiple builds.
Durability is a key aspect of the design, as these washers must withstand significant mechanical stress and heat during firing. AccuWashers are made from heat-treated 400 series stainless steel, a material chosen for its strength, corrosion resistance, and ability to maintain structural integrity under high temperatures. The washers are typically finished with a matte or oxide-blasted surface to reduce glare and improve corrosion resistance. Their monolithic construction prevents deformation, shear, or compression under torque, which is a common problem with crush washers. As a result, they maintain consistent alignment even after repeated use or exposure to recoil forces and environmental conditions.
Another important advantage is the system’s overall value. Although the initial cost of an AccuWasher kit is higher than a basic crush washer, it provides multiple washers in one package and can be reused across several installations. A single kit can typically service multiple muzzle devices, often aligning several brakes before replacement washers are needed. This reusability, combined with the increased safety and precision it offers, makes it a cost-effective choice for enthusiasts who frequently modify or maintain their firearms.
Overall, Precision Armament’s AccuWashers represent a significant advancement in muzzle device alignment technology. By combining extremely tight machining tolerances, durable stainless steel construction, broad compatibility, and a simplified single-shim approach, they deliver a level of precision and reliability that traditional systems struggle to match.
The Precision Armament’s AccuWasher system can be located at Brownells:
Check out PRECISION ARMAMENT AccuWasher AW500 Gen2 Shim Kit - 1/2-28 .725" SKU: 430113318 with 3 reviews and an overall rating of 4.3,
