Out of stock
YHM BARREL SHIM SET AR15 1/2 INNER DIMENSION
$8.50
$9.95
(You save
$1.45
)
- Firearm Group:
- AR Platform
Getting your AR-15 muzzle device timed correctly matters—whether you're running a flash hider, brake, or suppressor adapter. The Yankee Hill Machine AR-15 Barrel Shim Set is a precision tuning tool that lets you dial in perfect timing without guesswork. This 1/2" inner diameter shim set works with Yankee Hill's 5.56mm quick-detach muzzle brakes and other compatible devices, giving you the micro-adjustments needed to achieve the exact rotational alignment your setup demands.
Timing a muzzle device isn't just about noise or recoil control—it affects how your brake or hider performs and how cleanly your device seats when you attach or remove it. Rather than grinding away material or settling for close-enough, a shim kit lets you build up the precise thickness needed for spot-on timing. Yankee Hill includes a carefully chosen range of shims so you can fine-tune for your specific barrel diameter and device profile.
This is the kind of detail that separates a clean, reliable AR build from a frustrating one. Whether you're a competitive shooter chasing consistency, a hunter who wants a hider that works as designed, or just someone who builds their own rifles, having the right shims on hand means you won't be improvising with tape or leaving performance on the table.
What's Included
- 2× 0.002" shims for micro-adjustments
- 5× 0.005" shims for incremental tuning
- 1× 0.020" shim for larger gaps
Specifications
| Inner Diameter | 1/2" |
| Barrel Thread Pattern | 1/2" × 28 (5.56mm) |
| Total Shims Included | 8 |
| Manufacturer | Yankee Hill Machine Co |
Frequently Asked Questions
Will these shims work with my muzzle brake?
These shims are designed for use with Yankee Hill Machine's 5.56mm quick-detach muzzle brakes and other compatible 1/2" × 28 threaded devices. If you're using a different brand, verify that your muzzle device accepts shims and has a 1/2" inner diameter.
What does timing a muzzle device mean?
Timing refers to the rotational position of your muzzle device when it's fully threaded onto your barrel. Some designs (like flash hiders and brakes) perform best when oriented a specific way—slots up, baffles aligned, or ports symmetrical. Shims let you adjust how far the device screws on so it stops at the correct rotational position every time.
How do I know which shim thickness I need?
Start by threading your muzzle device on as far as it will go, then rotate it to where you want it timed. Measure the gap between the device shoulder and your barrel shoulder. The shim set gives you options from 0.002" up to 0.020", and you can stack multiple shims to reach any thickness in between.
