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CMMG
AR-15/M16 300 BLK BARRELS

815835062761 100014823

Description
Ratings (5)

Converts Your AR To A Hard-Hitting .30 Caliber Round With No Other Modifications

Direct replacement for the standard .223/5.56mm barrel converts your AR-15 to the high-performance 300 AAC Blackout (300BLK) cartridge. The 300 AAC lets you upgrade your rifle to 7.62 x 39 ballistics, while retaining the standard AR-15/M16 bolt, carrier, and magazine at its full capacity, with no additional modifications. 1-7" rifling accepts bullet weights from 110 gr to 220 gr, and 5/8"-24 muzzle threads accept popular AR-.308 flash suppressors and muzzle brakes. Three models available, 16", 12.5" and 8.2" long and treated inside and out with CMMG’s "Wasp" nitriding process for outstanding resistance to wear and corrosion. 16" barrel has the gas port in the standard position for use with all M4-length gas systems and supersonic ammunition. 12.5" & 8.2" barrels have the gas port positioned for use with pistol-length gas systems.

SPECS: Hardened 4140 chrome-moly steel, Wasp nitride finish, matte black .750" O.D. at gas port.5/8-24 muzzle threads.

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Customer ratings for CMMG AR15 12.5" 300BLK MR BARREL

Number of ratings: 5
From brownells.com: 5
Average rating: 3.6

great barrel (22/04/2012)

The barrel was great. I love the finish and fit. It is ballanced well too. I did have a few "hiccups" so to speak. Still working through it, it may be a break in issue. So far I've only shot about 20 handloads of 110 grain Nosler BT. I had a few issues with the rounds fully chambering feeding from the magazine, it wouldn't fully chamber the round. I could eject the round and load it one at a time, and it works fine. That is the reason for the 4 stars. The accuracy is very good so far, still working on the hand loads and T & E and I haven't stretched it out yet. The recoil was very light for a 30 caliber round.

Working well for my build (26/04/2012)

Had some FTF in the beginning, but they've seem to have settled down on the second test. Overall I'm satisfied with the product and cannot complain. I noticed by posting through the 300blktlk forum that the gas port hole is not ground like it should be in order to provide a proper match with the gas block. I also had to make sure my gas block was PERFECTLY centered, otherwise there wasn't enough gas to chamber the next round. (short stroking)

Honestly, when I do my next one I will not be using a CMMG barrel. Wilson is only a few bucks more.

Updated Review (26/11/2012)

The problem I previously spoke of was related to a magazine issue. I've used a Mag Pul 20 round and not had any issues, since. It is very accurate and reliable. I've since shot a deer with the 125 grain Nosler hand loaded Ballistic tips and it dropped in its tracks. I'm very pleased with the barrel and caliber choice.

2 barrels will not head space (17/02/2014)

I was building a pair of rifles for friends. I have built 300 AAC rifles using the Brownells barrel with no issues. The fit and finish on these barrels looked great but they would not head space with the "go" gauge. I tried several bolts from several manufacturers including a well used Colt bolt. These chambers are way off!

Awesome barrel (11/07/2014)

I was looking for a lighter weight barrel for a carbine project, CMMG makes this one at a weight of only 1.8# and coupled with a Midwest Industries 10" lightweight kemod rail the rifle turned out to be all I expected. Sight in with iron sights took five shots and from that point my old eyes could easily keep it in the black. This rifle will be tested on Texas hogs soon.

Read 5 more ratings on brownells.com

224.9 259.9 3 GBP

Product no.: 100014823
CMMG AR15 12.5" 300BLK MR BARREL
Mfr Part: 30D8A0A 815835062761 Direct replacement for the standard .223/5.56mm barrel converts your AR-15 to the high-performance 300 AAC Blackout (300BLK) cartridge. The 300 AAC lets you upgrade your rifle to 7.62 x 39 ballistics, while retaining the standard AR-15/M16 bolt, carrier, and magazine at its full capacity, with no additional modifications. 1-7" rifling accepts bullet weights from 110 gr to 220 gr, and 5/8"-24 muzzle threads accept popular AR-.308 flash suppressors and muzzle brakes. Three models available, 16", 12.5" and 8.2" long and treated inside and out with CMMG’s "Wasp" nitriding process for outstanding resistance to wear and corrosion. 16" barrel has the gas port in the standard position for use with all M4-length gas systems and supersonic ammunition. 12.5" & 8.2" barrels have the gas port positioned for use with pistol-length gas systems.

259.9 GBP 7 £259.90 *

Is a 'Call to order' product.

Delivery time approx. 7-14 days.
7 pcs. in the USA warehouse

Specs: Cartridge: 300 AAC Blackout Contour: Medium Finish: Nitride Gas System Length: Pistol Length: 12.5'' Make: AR-15 Muzzle Threads: 5/8-24 Twist: 1-7

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Restrictions

Is a 'Call to order' product.

Top takeaways

Converts AR-15 to 300 AAC Blackout using standard bolt, carrier, and magazine without additional modifications.
Features a 12.5" medium contour barrel with 1-7" twist, suitable for 110 gr to 220 gr bullets, and a pistol-length gas system.
Constructed from hardened 4140 chrome-moly steel with a nitride finish for superior wear and corrosion resistance.

Attributes

Cartridge: 300 AAC Blackout Contour: Medium Finish: Nitride Gas System Length: Pistol Length: 12.5'' Make: AR-15 Muzzle Threads: 5/8-24 Twist: 1-7 Delivery weight: 0.816kg

Item details

Made in USA
US export classification: 0A501.c

Product no.: 100009125
CMMG BARREL STRIPPED 16" M300 LE AAC W/CAR GAS
Mfr Part: 30DF80A 815835011028 Direct replacement for the standard .223/5.56mm barrel converts your AR-15 to the high-performance 300 AAC Blackout (300BLK) cartridge. The 300 AAC lets you upgrade your rifle to 7.62 x 39 ballistics, while retaining the standard AR-15/M16 bolt, carrier, and magazine at its full capacity, with no additional modifications. 1-7" rifling accepts bullet weights from 110 gr to 220 gr, and 5/8"-24 muzzle threads accept popular AR-.308 flash suppressors and muzzle brakes. Three models available, 16", 12.5" and 8.2" long and treated inside and out with CMMG’s "Wasp" nitriding process for outstanding resistance to wear and corrosion. 16" barrel has the gas port in the standard position for use with all M4-length gas systems and supersonic ammunition. 12.5" & 8.2" barrels have the gas port positioned for use with pistol-length gas systems.

239.9 GBP 5 £239.90 *

Is a 'Call to order' product.

Delivery time approx. 7-14 days.
5 pcs. in the USA warehouse

Specs: Barrel Weight: 2.205 lbs Cartridge: 300 AAC Blackout Contour: Medium Finish: Black Gas System Length: Carbine Length: 16'' Make: AR-15 Muzzle Threads: 5/8-24 Twist: 1-7

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Product no.: 100014824
CMMG AR15 8.2" 300BLK MR BARREL
Mfr Part: 30D810A 815835016283 Direct replacement for the standard .223/5.56mm barrel converts your AR-15 to the high-performance 300 AAC Blackout (300BLK) cartridge. The 300 AAC lets you upgrade your rifle to 7.62 x 39 ballistics, while retaining the standard AR-15/M16 bolt, carrier, and magazine at its full capacity, with no additional modifications. 1-7" rifling accepts bullet weights from 110 gr to 220 gr, and 5/8"-24 muzzle threads accept popular AR-.308 flash suppressors and muzzle brakes. Three models available, 16", 12.5" and 8.2" long and treated inside and out with CMMG’s "Wasp" nitriding process for outstanding resistance to wear and corrosion. 16" barrel has the gas port in the standard position for use with all M4-length gas systems and supersonic ammunition. 12.5" & 8.2" barrels have the gas port positioned for use with pistol-length gas systems.

224.9 GBP 3 £224.90 *

Is a 'Call to order' product.

Delivery time approx. 7-14 days.
3 pcs. in the USA warehouse

Specs: Cartridge: 300 AAC Blackout Contour: Medium Finish: Nitride Gas System Length: Pistol Length: 8.2'' Make: AR-15 Muzzle Threads: 5/8-24 Twist: 1-7

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🔥 Upgrade your AR-15 with CMMG's 12.5" 300BLK MR Barrel for superior performance! 🎯 Nitride finish, 1-7 twist & 5/8-24 threads. Shop now & transform your rifle! 💥

Description
Ratings (5)

Converts Your AR To A Hard-Hitting .30 Caliber Round With No Other Modifications

SPECS: Hardened 4140 chrome-moly steel, Wasp nitride finish, matte black .750" O.D. at gas port.5/8-24 muzzle threads.

More...

Customer ratings for CMMG AR15 12.5" 300BLK MR BARREL

Number of ratings: 5
From brownells.com: 5
Average rating: 3.6

great barrel (22/04/2012)

Working well for my build (26/04/2012)

Updated Review (26/11/2012)

2 barrels will not head space (17/02/2014)

Awesome barrel (11/07/2014)

Read 5 more ratings on brownells.com

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