WMD NiB-X Nickel Boron Bolt 5.56/.223/300BLK

Manufactured by WMD Guns
Manufactured by WMD Guns
2 Reviews

Out of Stock

NOTE: Limit 5 per household. Quantities exceeding 5 will not allow checkout.



This complete AR-15 Bolt assembly comes pre-built with gas rings, extractor, and ejector. The bolt itself features WMD's proprietary NiB-X nickel boron coating which offers a high-lubricity for drastically reduced wear, maintenance, and oiling, and harder-than-chrome surface that will hold up to thousands of rounds of use. As an added benefit, it is also extremely easy to clean.
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Bolt FinishNickel Boron
Bolt MaterialCarpenter 158 Steel
BrandWMD Guns
Caliber Gauge5.56 NATO
High Pressure TestedHigh Pressure Tested
Magnetic Particle InspectMagnetic Particle Inspected

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see www.p65warnings.ca.gov

Ratings & Reviews

2 reviews

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  • 1 star
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head space


The bolt arrived on time and was what I needed to address a head space issue with a WMD barrel I had installed a Zero fail bolt but it what not gauge correctly with the WMD barrel it is now perfect.



This device is amazingly rugged. Even with brute force and pliers banging up against it on accident.Just be sure to clean up the firing pin hole. Also, clean up the hole for the cam pin too! There may be excess carbon from testing. If you got the NiB-X cam pin, it's a super tight tolerance fit.