HM Defense AR-15 5.56/.223 HMB Battle Bolt Carrier Group - Black Nitride - HMB-BCG-AR15
In stock
The HMB Bolt corrects a natural weak point in existing Mil-Spec M16, AR-10 & AR-15 bolts where the cam pin hole passes through the bolt. Under extensive use, including the stress of combat, a standard Mil-Spec bolt can fail at the cam pin hole location. The HMB Bolt by HM Defense eliminates the pass-through cam pin hole and replaces it with a cam pin socket and tapered cam pin design. This new patent-pending design eliminates the natural weak point of Mil-Spec bolts by significantly increasing the amount of metal (and strength) at the cam pin location. The result – No more broken bolts! Additionally, the HMB Bolt reduces contact between cam pin and firing pin, enabling smoother operation of firing pin, bolt lugs and aft gas rings. The new cam pin socket also retains lubrication for extended operations.
BOLT CARRIER GROUP SPECIFICATIONS
- Manufacturer: HM Defense
- Manufacturer Part #: HMB-BCG-AR15
- Type: Bolt Carrier Group
- Color: Black
- Finish: Nitride
- 5.56 NATO – 223 Rem – 300 AAC
- 9310 Steel
- 4340 Hardened Steel Cam Pin
- Nitride Black Finish
| Weight | 12.72 oz |
|---|---|
| Bolt Material | 9310 Steel |
| Cartridge Compatibility | .223/5.56 NATO/.300 BLK |
| Finish | Chrome |
| Carrier Profile | M16 |
| High Pressure Tested | Untested |
| Magnetic Particle Inspected | None |
| Platform | AR-15 |
| Bolt Finish | Nitride / Melonite |
| MPN | HMB-BCG-AR15 |
| UPC | 854164007142 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
Customer Reviews
- Reviews
- Questions
Decent BCG with a few caveats
BCG gauged very well, very very efficient. The carrier key was nice and tight with good staking and no obstructions and good screws. Nitriding is also good and they skip the extractor claw which is good. What's not good is the ejector spring was just borderline too weak at about 7lbs which Chad at SOTAR and I concluded could have been from a slightly deeper hole. Installing a spring co bumped it up to 8.5. Everything else was fine though. Would recommend, but may want to opt for KE Arm's bolt since the carrier, aside from being gas efficient is nothing too special. 4 stars for the carrier easily, but if you're just after the bolt opt for maybe one at KE Arms which is chrome plated.
USGreat BCG
Great BCG. Sturdy and high quality design.
USVery nice fit and finish!
This BCG appears to be very high quality. After only a few hundred rounds it has shown that it functions flawlessly
USHigh expectations
Everything I can see and feel with this BCG is on par with other BCG's in the same price range. While I know I can still experience bolt failure at the lugs, I have peace of mind that the bolt will likely not break at the cam pin, due to the improved design.
USSuper good quality
I’ve purchased about 3 of these now for various ar builds and you can’t beat the quality after you take it to the range for the first time you can feel the difference
