AR15 Bolt Assembly

Bolt Assembly - Complete

Bolt assembly for M-15/M-16 or M-4 machined from Mil-Spec Carpenter No. 158® steel, shot peened for increased strength per Mil-Spec, includes Mil-Spec 8620 tool steel extractor w/ viton insert and improved design spring that dose not require an o-ring, Mil-Spec ejector and spring. 

HPT (High Pressure Tested) and MPI (Magnetic Particle Inspected)

Complete Mil-Spec Bolt includes:

  • Mil-Spec Carpenter 158® steel
  • Shot Peened for Increased Strength per Mil-Spec
  • High Pressure (HPT) and Magnetic Particle (MPT) Tested
  • Tool Steel Extractor Assembly (spring with viton insert, pin, extractor)
  • Mil-Spec Ejector Assembly (ejector, spring, roll pin)
  • Gas Rings - Set of 3
  • Comes Assembled
Calculated at checkout
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    1. Nitride Bolt

      Shipped super fast. Even coating with zero defects. Fits in the barrel extension of my 357AR perfectly with no trimming required and no additional headspacing necessary. Will recommend to others and purchase again. on 10th May 2018

    2. Beautiful product!

      The fit and finish is beautiful, customer service was great ! I have not shot my rifle yet because it's freezing in Chicago, highly recommend this product if u want the best bolt and guts for your rifle ! on 20th Dec 2016

    3. Best bolt/BCG I've ever used

      This is the best product and company I have done business with in a long time. They respect their customers they have a great warranty that they truly stand behind and if you need to email them to get more information they are always quick to respond and on top of it. I work in a gun store and recommend their products highly and have had co-worker order from them as well ( he was very impressed with his NiB BCG ) and also now highly recommends them to put customers trying to finish their builds or just as an upgrade to the standard BCGs. Love this company and their product. on 12th Oct 2016

    4. Bcg

      Finish looks good but no time to try it out yet. I will use it to replace semi bolt on my lot. Keep the lot bcc as a spare for my rifles. Shopped in a timely manner without problems. on 22nd Feb 2016


      This Coating is superior to any other. Besides the coating the owner is always making sure the parts he uses are only the best, if he finds any issues he wont sell them. The other thing about buying this product is the customer service, I have Ordered other pars from many other popular companies and have been in the resale business for over 20 years and no one has impressed me like the owners with Cryptic Coatings. I enjoy speaking with them every time and they take care of their customers. on 11th Aug 2015

    6. Nothing but the best

      I had ordered a bolt carrier group in the mystic bronze and was extremely pleased with it. It wasn't until after I had that installed I realized I wanted the bolt and cam pin to go with it. They didn't have an online option to coat just the bolt. I got ahold of Cryptic Coatings to see what they could do and it was in the mail shortly after. Very happy with everything. Fit and finish is perfect! Definitely will buy from Cryptic Coatings again. on 5th Jun 2015

    7. great bolt

      This is the nicest AR bolt I have ever dealt with. The tolerances are superb. I wish I had known about cryptic coatings when I first started my build. The customer service is first rate. My only regret is not getting my complete BCG from here. But my next build will run a full cryptic coatings BCG. Thank y'all. on 8th Mar 2015