Completing Builds and Swapping Calibers is Easy with Rock River Arms Complete Uppers
Rock River Arms is well-known for the quality firearms they have been producing for decades. Their guns are used every day by military and law enforcement professionals, hunters, target shooters and shooters of just about every type. Rock River Arms complete upper receivers are a fantastic way to finish off a rifle build project or to quickly and easily swap calibers on your favorite AR-15.This complete upper receiver is chambered in .450 Bushmaster. It features a 16" chrome moly steel barrel which is fitted with a muzzle brake to help reduce felt recoil for more accurate follow-up shots. A lightweight aluminum free float handguard with M-LOK slots allows for the easy addition of M-LOK compatible accessories such as bipods, foregrips, lights and more. This upper includes a bolt carrier group, charging handle, and a magazine and it is ready to attach to any standard AR-15 lower receiver.
Rock River Arms Complete Upper Specifications and Features:
- Rock River Item Number: 450B0592
- AR-15 Complete Upper Receiver
- Caliber: .450 Bushmaster
- 16" Chrome Moly Steel Barrel
- Twist Rate: 1:24
- Threaded 5/8x32 TPI with RRA Operator Muzzle Brake
- Mid Length Gas System with Low Profile Gas Block
- Forged Aluminum A4 Flat Top Upper Receiver
- RRA 13" Extended Lightweight Aluminum Free Float M-LOK Handguard
- Full Length Picatinny Top Rail
- Matte Black Finish
- Mil-Spec AR-15 Lower Receivers
- Bolt Carrier Group
- Mil-Spec Charging Handle
- (1) 5-Round Magazine