$248.99
8 in stock
Online inventory may differ from in-store availability.
Quick turnaround so you get your gear sooner.
Trusted checkout with industry-standard protection.
Keeping Traditions Alive Since 1953
Secure Transactions provided with 
The heart of any .308 AR is the bolt carrier group, and CMMG doesn't cut corners on the MK3. This is a fully assembled unit ready to drop straight into your rifle or upper build, so there's no fussing with individual parts or hoping everything headspaces right. CMMG has built a solid reputation for quality control, and this BCG is a good example of why folks trust their name on a build.
The bolt is machined from 9310 steel, which is the standard a lot of serious builders look for thanks to its core hardness and fatigue strength under the heavier bolt thrust a .308 generates. The carrier itself is 8620 steel with a chrome-lined interior, and the whole assembly wears a black phosphate finish that shrugs off wear and holds oil well. One detail worth calling out is the extractor, which CMMG cuts from S7 tool steel. That's a step up from the usual, and it's the kind of part that tends to hold up round after round when a lesser extractor would start giving you feeding headaches.
This carrier group follows the DPMS-pattern layout, so it's designed to work in most .308 and 7.62×51 AR-10 style rifles and uppers built to that spec. If you're running a CMMG MK3 rifle or upper, it's a natural match, but it plays nicely with plenty of other DPMS-pattern platforms too. Since .308 ARs aren't as standardized as their 5.56 cousins, it's always smart to confirm your upper and barrel extension are cut for the DPMS pattern before ordering.
Whether you're finishing off a fresh build or replacing a worn or subpar BCG, this one gives you a dependable, no-drama option from a name that knows the platform inside and out. It's the kind of part you install and then stop thinking about, which is exactly what you want out of the component doing the hardest work in your rifle.
It's built to the DPMS pattern, so it will fit most .308 and 7.62×51 AR-10 style uppers and rifles cut for that spec. .308 ARs aren't standardized the way 5.56 rifles are, so it's worth confirming your upper and barrel extension follow the DPMS layout before ordering. If you're running a CMMG MK3 rifle or upper, it's a direct match.
This is a complete, fully assembled bolt carrier group. The bolt, carrier, extractor, cam pin, and firing pin are all included and ready to go, so you can drop it right into your rifle or upper build with no extra assembly.
The extractor is one of the hardest-working small parts in the gun, and it's a common failure point on cheaper BCGs. S7 tool steel is tougher and more wear-resistant than the standard material, which helps it keep grabbing and pulling cases reliably over a lot of rounds. It's a quality touch that pays off in long-term dependability.
Yes, black phosphate is a proven, hard-wearing finish that's been the mil-spec standard for good reason. It resists wear and holds lubricant well, which helps the moving parts stay slick and protected. Keep it oiled like any BCG and it'll run a long time.
| UPC | 815835012483 |
|---|---|
| Manufacturer | |
| Manufacturer Part Number | 38BA423 |
| Model | |
| Product Type | Bolt Carrier Group |
| Color | Black |
You must be logged in to post a review.
Reviews
There are no reviews yet.