Rock River Arms A4 Mid-Length Complete Upper .450 Bushmaster 16in 1:24 M-LOK
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Rock River Arms A4 mid-length complete upper receiver chambered in .450 Bushmaster. 16-inch chrome moly barrel with 1:24 twist, mid-length gas system with a low-profile gas block, and an RRA Operator Brake with 5/8-32 threads. A 13-inch M-LOK compatible lightweight free-float rail provides a rigid mounting platform for accessories. This upper arrives ready to install with a bolt carrier group, charging handle assembly, and one 5-round magazine.
Specifications
- Manufacturer:
- Rock River Arms
- Category:
- upper-receiver
- Platforms:
- AR-15
- Interfaces:
- Magpul M-LOK
- UPC:
- 8229062180986
- MPN:
- 450B0592
- Required Component:
- Yes
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