Hey all,

I thought someone here might be able to answer me this concern. I was told by a friend that it's dangerous to swap out bolt carriers between AR type rifles, meaning that if I buy a new upper, I should get it with a new bolt/bolt carrier as well and pay the extra cost. I thought that only the *bolt* and not the bolt carrier was what needed to be matched to the chamber. So... bottom line: can you switch bolt carriers, bolts, both, or neither between uppers without any worry? Thanks,

-Robert

P.S. I heard this had something to do with the headspace, if that helps anyone.

Just keep the bolt with the upper and you'll be fine.  Bolt carriers are basically interchangeable.  JMHO

Steven L.

Yep, just the bolt.

Welcome to AR15.com!

Robert, you are correct, only the bolt head spaces with the barrel extension.  The carrier can be swapped, but if the rifle is not new, bolts and barrels should be kept together, unless headspace is checked first.  As a matter of reality, bolts and carriers will wear together as a unit, and with the upper due to minor inconsistencies in metallurgy, dimensions and quality of production.  It is generally considered a good idea to keep a bolt and carrier assembly with an upper as they wear together, but it is not critical for safety's sake to keep the same carrier.

Ive heard this too. But is not absolute, As one of my Bolt and Carrier has seen three differnt barrels. Another Bolt and Carrier has had two Barrel changes.......But if you have the $$ go ahead and keep them together.  Also mentined is to check the Headspace.............BTW these two carbines run run run  never had a problem

Thanks guys. I really appreciate it. I'm sure I'll be asking more questions as time goes on... there's lots of stuff I dying to learn. Heck, maybe someday I'll be able to help out with other people's questions.

-Robert