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CMMG
Overview
The CMMG AR-15 8.2" 300 Blackout MR Barrel is designed for those looking to maximize the performance of their compact builds. With a medium profile and a pistol-length gas system, this barrel offers a balance of stability and maneuverability, making it ideal for close-quarters applications. Its 1:7 twist rate helps stabilize a wide range of bullet weights for enhanced accuracy. This barrel is frequently found in builds specifically configured for the 300 Blackout caliber, catering to shooters who prioritize versatility and effectiveness in short-range engagements.
Specifications
Available Merchants(9)
Prices checked
Price Alert
October 2026 on GunPartPicker
CMMG AR15 8.2" 300BLK Mr Barrel ranked #131 of the 329 barrels builders added on GunPartPicker in October 2026. Builders have added it to their builds on GunPartPicker. Since April 2026, it ranks #44 of the 1,047 barrels builders have added. Builds with this barrel are nearly all chambered in 300 Blackout, nearly all on pistol-length gas, and nearly all AR-15.
It was in stock most times we checked in October 2026, but today only CMMG has it in stock. It dipped to $153.99 at Ammunition Depot for a stretch in October 2026, well under its usual $199.95, so sales do come around. Buying today, the lowest price is $199.95 at CMMG, above October's low of $153.99, so a better deal may come back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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Frequently Built With
The part most often added in each category by the builds that include this one
Aero Precision M4E1 Threaded Stripped AR-15 Upper - No Forward Assist - Anodized Black
Aero Precision AR-15 Breach Charging Handle Ambidextrous Small Levers
Silencerco AR-15 Billet Lower Receiver
Midwest Industries Suppressor Series M-LOK AR-15 Handguard - 10.5"
Aero Precision AR-15 5.56 BCG W/C158 Bolt - Aero Logo - Phosphate
Aero Precision Gas Tube, Pistol Length - Stainless Steel
Builds Featuring This Part
See all builds →Builds in the community that include the Cmmg Ar15 8.2" 300blk Mr Barrel
| Build | Parts | Total |
|---|---|---|
 | 17 | $2115.14 |
 | 16 | $2830.23 |
| 7 | $965.85 |
 | 20 | $1972.00 |
 | 17 | $1477.97 |
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