OK, This is a long awaited followup on this post and it doesn't provide complete satisfaction to the image of a broken bolt photo above. But, reality is often something different than the idea. Finally in December I got a phone call from Rock River Arms telling me that the Complete Bolt Carrier Group that I back ordered in early March of 2012 has not been shipped and that they were were just then getting to orders placed in January of 2012. . . . .They did assure me that they would eventually fill that order but couldn't say when that would be. Yeah.
So with that as my guide I decided to take another look at the broken bolt and see what could be done. (Background: I grew up in a precision machine shop with much of the extended family in the same business.) So i contacted a cousin that had recently purchased some new lathes and also has similar experience with heat treating and precision machining. Without a New RRA bolt to look at and see what they had changed to improve the design we had to make some educated guesses. The plan we came up with was to get the right type of steel in Bar form. Have a Precision Certified Welder weld a solid Bar if Thicker stock on the back of the Bolt. Turn it to a greater OD and bore it to a precise ID and face it down to the precise length to work for proper lockup to match the existing bolt. This is still in process and I will post Photos of the repaired and heat treated bolt.
Preaviously posted photos early in this thread.
This image is hidden for guests. Please log in or register to see it.
This image is hidden for guests. Please log in or register to see it.
Interesting. If it works out, make sure your friend sets up a link to his site, if and when he gets one, and he may end up with some business from our site from guys in a bind. :thumbs:
I'm very interested in the end result of this and please, consider what I said as serious because if this works, it COULD be a whole new source of income for the guy doing it with the market for parts being what it is...
Thanks for the input and I truly hope this works for you.
Will do. Rick is a Precision Machinist of 30+ years and has done years of gun repair and modification so he not only has the machining experience but the knowledge of the specific problems introduced by firearms function. We also are using a welder that has specific certifications with some of the large aircraft manufacturers so he understands the importance of marrying materials and heat and penetration of the weld. we will also rely on his experience of weather we need to re-heat treat the entire bolt again or (Since we are specifically talking about the tail end) if we have not softened "Annealed" the front half of the bolt enough to require heat treating it completely again. We will be using a Rockwell Tester both before and after to determine the hardness of the bolt fore and aft just to be sure. Not all guess work. Of course we will test it all on a sled with a string not with my face as a blast dampener. ;-P
Alrighty then! Man I can't believe it's been this long and you still haven't gotten the new BCG from RRA. Glad I ordered mine when I did! If you go back to about page 6 or so of this thread, you'll see my side by side pics of old and new bolts. I honestly think they only beefed up the bolt tail diameter from 1/4" to 5/16" and bored the bolt carrier out to match. Of course they also changed the design of the extractor etc, but that won't be necessary for you. I've had zero problems since getting my new BCG. I certainly hope it works for you. You and your friend seem to have access to some really nice equipment etc :thumbs: .
Also, if you wind up ruining your bolt I have another one just like it! If you get it fixed with no problems, I may be your first customer as well. Always good to have a spare BCG laying around...... Thanks for the update.
Wondering if this thread is still read by some of the previous posters...has the issue been resolved with the new manufacturing of the bolt? Were the parts received from Rock River, and what was the price? All great information! Since I was searching for information about the barrel markings on MY Bushmaster .308, I found your forum, got lost in it and subsequently looked at my bolt. Got home that night, opened the safe, pulled out the bcg to discover...(dun dun dun!) a broken bolt. Last visit to the range, all was fine. Currently have an email in to Rock River for price and compatibility, as their catalog touts "commonality is by choice, not by design". Hoping for a smooth resolve.
All content of this site is copyright 2003 - 2017 AR-10(T)™, AR-10™, are trademarks of ArmaLite, Inc.® AR10T.com is NOT endorsed or affiliated with ArmaLite, Inc.®
About AR10T.com
AR-10(T) is a community focused on rifles, optics, scopes, gear, accessories, and components used by the professional operator and skilled marksman. Enthusiasts, shooters, and gunsmiths alike contribute to our gallery, articles, and reviews Thank you for visiting!