All the below information is taken directly from the Ray-Vin website.
Brandes Magnum Rimfire 22 Magnum AR 15 Uppers Features
- Right or Left hand
- 16-1/4″ or 18″ Stainless Steel fluted barrel
- Anodized aircraft aluminum upper
- Case hardened bolt
- Hardened S7 firing pin
- Case hardened ejector
- Case hardened feed ramp
- Free float hand guard
- 1/2-28 x .450 muzzle thread
- Two 14-round Black Dog magazines
- Accepts all AR free float handguards
- Accepts all flat top sight systems
Brandes Magnum Rimfire 22 Magnum AR 15 Uppers Include
- Fully assembled upper
- Including bolt
- Muzzle thread protector
- Two 14 round magazines
- A1/A2 buffer
- Car buffer
- Buffer spring
- Travel limiter
- Parts list
BMR Notes, a lesson in blow-back actions.
Performance: The BMR is a blow-back action. This type of action involves a balance of many factors such as cartridge power, case geometry and bolt mass. In the AR system, the bolt, the buffer and half of the spring weight constitute the bolt mass. Altering the mass of the buffer allows for tuning the action for a particular cartridge.
BMR 22WMR uppers function quite reliably using ammo with 40gr or heavier bullets.
Bullets lighter than 40gr, especially 30gr, will probably require some adjustment for satisfactory results.
It has come to our attention that CMC triggers do not perform with our upper system. Light strikes is the problem reported with CMC triggers. The CMC trigger is engineered to work with AR-15 rifles firing 5.56 Nato or .223 Remington cartridges, and is not intended to work with other cartridges. The fine folks at CMC have told me they will replace the hammer spring with a stronger one at no charge.
If you are ordering a CMC trigger for our upper, call in the order and request a stronger hammer spring. While this may reduce light strikes, there is no guarantee either from CMC or Ray-Vin. We test our uppers using mil-spec triggers and hammers.
.22 Magnum AR-15 Buffers
Full Length Buttstock A2 Buffer Configuration – .22 Magnum
In the above configurations, the topmost is standard with the CAR recoil spring for 22WMR and 17HMR ammo. The lower configuration uses the standard A2 buffer with a travel limiter. Use this configuration if you experience case head doming or excessive un-burned powder in the action. The travel limiter is necessary to prevent the bolt handle from bottoming in the receiver slot.
Carbine Length Buttstock A4 Buffer Configuration – .22 Magnum
Similar to the A2 configurations, the uppermost is standard and the lower should be used if you experience case head deforming or excessive powder in the action.