Rock River Arms Tactical Carbine, 16″ Barrel, RRA 13″ Free Float M-LOK Handguard, Black, 5 Rounds

Product Description

The Rock River Arms 450 Bushmaster upper receiver delivers serious stopping power for your AR-15 platform. This complete upper assembly pairs a 16″ barrel with a mid-length gas system for reliable performance. Additionally, it features RRA’s Operator Muzzle Brake and a 13″ free-float M-LOK handguard for precision shooting.

Furthermore, this upper receiver comes fully assembled with the bolt carrier group and charging handle. No additional gunsmithing or assembly work is required. Installation is straightforward on any compatible AR-15 lower receiver.

Ideal for Caliber Conversion and Training

Whether you’re upgrading to a more powerful caliber or building a dedicated training platform, this 450 Bushmaster upper meets the demand. The mid-length gas system provides consistent cycling and reduced recoil impulse. Moreover, the 5-round magazine capacity ensures compliance across multiple states.

The free-float handguard design enhances accuracy by isolating the barrel from interference. Additionally, the M-LOK slots allow easy attachment of accessories and tactical gear. The anodized black finish resists corrosion and delivers a professional appearance.

Premium Rock River Arms Quality

Rock River Arms has built a reputation for precision-engineered AR components. Therefore, you can trust this upper receiver for durability and consistent performance. The complete assembly approach saves time and ensures proper fitment on AR-15 platforms.

Ordering from Western Sport

Order online and it ships straight to your door. Western Sport has been a licensed FFL/SOT dealer since 2007, and everything we sell carries the full manufacturer warranty. Questions before you order? Send us a message.

Frequently Asked Questions

Q: Will this 450 Bushmaster upper fit my AR-15 lower receiver?

A: Yes, this RRA upper receiver is designed to fit standard AR-15 lower receivers. The upper uses a standard AR-15 takedown pin and buffer tube interface. Make sure your lower is in good condition and compatible with mid-length AR platforms.

Q: Does Rock River Arms offer a warranty on this upper receiver?

A: Rock River Arms stands behind its products with a manufacturer warranty. We recommend contacting Western Sport or Rock River Arms directly for specific warranty details and coverage terms.

Q: What is the transfer process for buying this upper in Texas?

A: Since this is a complete upper receiver (not a lower), it does not require an FFL transfer in Texas. You can take it home the same day.

Q: What is the best use case for the 450 Bushmaster caliber?

A: The 450 Bushmaster is excellent for hunting medium to large game and provides superior stopping power for home defense. Its mid-length gas system and free-float handguard make it reliable for training and sport shooting as well.

Additional information