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. amazed!!

      nice and slippery but awesome coating on 2nd Sep 2019

    2. Perfection

      Purchased this complete bolt in Mystic Blue as a backup just in case, one of my Mystic Black bolts fail, (highly unlikely). Same excellent quality second to none. on 15th Jul 2019

    3. Simply the Best!

      I purchase a complete BCG in the mystic bronze back in 2016 and it has since been through about 5000 rounds on a 16" 556 upper and 9"300 blackout both suppressed and un suppressed. Not a single problem or heavy wear! I purchased a complete bolt assembly in the mystic black to put into the mystic bronze bolt carrier and it functions flawlessly. I used the mystic bronze bolt assembly for use in my 556 mil spec bolt carrier as a upgrade and it functions flawlessly as well. If you are wondering weather or not to go with this company just go with them and you will be more than satisfied! Gun cleaning has never been easier! I will never use any other bcg EVER! Also customer service is excellent... thanks Karen you are the best! on 11th Apr 2019

    4. Complete 5.56 bolt assembly cryptic blue

      Ok. Aside from the bolt being magnificent and super slick. Let me tell you about cryptic coatings themselves, great company. I had bought a cryptic silver complete bolt and wrote in my review stating that I really wanted the blue and was still waiting on one to come in stock for 5.56. Next day they emailed me saying they had some in stock. I order one , this was Thursday, they shipped it out that evening , it was at my house Saturday. Keep in my mind I only live a few hundred miles away, but still . Can't say enough good things about them. Great company, great customer service, selling great products. Can't ask for much more. on 28th Mar 2019

    5. Mystic Silver complet bolt

      Fast shipping, it was packaged good. Coating looks good and is pretty slick. Mystic silver wasn't what I wanted but after checking for several weeks for a mystic blue complete bolt, I settled for the silver since it was the only option besides NiB for a 5.56 bolt. Its a piston gun so I only needed the bolt and cam pin to finish. I'm still waiting on a mystic blue complete bolt to replace the mystic silver. " hint, hint " on 20th Mar 2019

    6. Superior products again and again. Mystic Black

      I want to personally thank everyone at Cryptic Coatings for their attention to detail as well as customer service. They took the time to make sure that my request was correct the first time. Needless to say, this is not the first or the last BCG that I will purchase from them. The last BGC i purchased still looks brand new and has had thousands of rounds cycled on it. Clean up is a breeze and it handles flawlessly. Thanks for a great, American made product. Sgt. Ed. on 20th Mar 2019

    7. Excellent Quality

      These bolts and carriers are amazing. They feel as though they are dipped in Teflon. This bolt headspaced perfectly to my Satern barrel though I haven't tried it with anything else. Every chamber is different but these are worth a trial. on 18th Mar 2019

    8. 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

    9. 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

    10. 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