Product Overview
Picking a barrel for an AR-15 usually means working out the gas system length, gas block size and muzzle thread yourself, then installing it like a gunsmith, with a torque wrench and an armorer's wrench. With MBZ, you just choose the caliber and the length, and the kit ships complete with the barrel ready to swap.
Every MBZ Barrel Kit is built by MBZ in Evansville, Wisconsin, and ships ready to install.
300 BLK 8" barrel, delivered with the MBZ Barrel Adapter mounted, ready to swap onto your MBZ-15 or MBZ Complete Upper Assembly into a short, quiet-friendly 300 Blackout in a few minutes. The MBZ Barrel Adapter comes mounted, so the barrel is ready to swap.
Good to know
An 8" barrel is for a pistol lower or a registered short-barreled rifle. Mounting it on a rifle lower is a federal offense, and some states restrict short barrels; check your state law before ordering. Supersonic and subsonic 300 BLK loads both run in this barrel; gas settings are Dan's call to confirm for suppressed use
What's in the box
- Ballistic Advantage barrel, 300 BLK, 8"
- 1:7 twist, 5R rifling
- Chrome-moly-vanadium steel
- Pistol-length gas system
- 5/8x24 muzzle thread with A2 flash hider
- MBZ Barrel Adapter mounted
- Low-profile gas block and gas tube
- Spanner wrench
Runs on
Your standard 5.56 bolt assembly and 5.56 magazines. No bolt change, no magazine change.
Runs on the standard .378 bolt assembly and standard AR-15 magazines.
Your MBZ-15 or MBZ Complete Upper Assembly came with the bolt assembly for its first barrel. If that first barrel was a 6.5 Grendel, a 6mm ARC or a 7.62x39, you will need the .378 bolt assembly for this kit. Keep the other one, you will want it if you go back.
How the swap goes
Remove any rail accessories, unscrew the handguard, swap the barrel, snug the Adapter with the wrench and give it a light tap. No torque wrench, no gunsmith. Screw the handguard back on. Recheck the Adapter when you clean the rifle..
