I am new to this site and appreciate all of the wisdom you all can offer a newbie.

I have a new Bushmaster 16" Post Ban Dissapator that I built from a stripped lower and am very happy with it.  It cost me more and now I know how everthing works and have a tool kit and spare parts to keep things working...

I wish to build a scoped long range A3 upper with a 24" barrel and I am considering sharing the bolt carrier assembly between the two uppers.  Is this a good or bad idea???

I am new to the site and I hope this is not subject that has been covered in great deal already.

TIA

Happy and safe shooting!

no don't do it. I'm in the Army and its an absolute no no. lol welcome to the boards and
if you want take a trip over to the Darkside.
thanks
john

First, let me welcome you to the site! [beer]

There have been discussions on this topic in the past but it doesn't hurt to ask. It is recomended that you not swap back and forth through your rifles. That said, I have heard of plenty of people doing it. I have also done it myself for awhile. I think that it will be up to you.

Depending on where you are going to get your upper from, it may be just as economical to buy a parts kit for just a few bucks more. At least this way you will have the extra parts and a complete B/C assembly to go with it.

Hey, you guys are great and thanks for the quick response.

My thinking was I could save 119.00 for the bolt carrier assembly and have complete bushmaster solution for up close action and log range action.  I guess sharing the bolt carrier between the two different uppers will just lead to mediocraty where designated bolt carriers for each individual uppers will lead to a broken in ton of accruacy?

Any body else sharing bolt carriers between different uppers?  Give us your thoughts...

Happy shooting

While not "preferred".... with a new BOLT (carrier does not matter), and two new  and in-spec uppers, there are no real safety risks.

The theory is, that the bolt face wears over time, as does the chamber.  Over a long time, thei will yield a headspace that opens up.  Putting a worn or out of spec bolt, in a worn/out of spec chamber, could possibly yeild excessive headspace.

Worst case scenario, buy a gauge or have it check out in both rifles, and shoot away.

I did it with my first two rifles for the same reason, I was too cheap.

But It got to be a pain, and I wanted both rifles at the ready, so eventually I got one for each.... and continued that with each rifle.  But I have no issue with swapping them out today, and do it all the time to help others function check their rifles for troubleshooting when they have failures.

No reason not to switch carriers between units, at least until you can afford one for both. The carrier is much harder than what it is riding in, so you aren't going to hurt it that way. All parts being made to the same spec, the bolt should (get the headspace checked, just in case!) fit either/both barrels the same. Have done it and seen it done with no ill effects, again, check headspace, just in case an out of spec bolt or barrel extension got thru QC.

good points!  I will heed your wisdome,

I bought a Bush 16" M4 and instantly got into high power competitions and started upgrading everything. The first thing I did was put a 20" upper on the M4 lower... and I used my existing bolt and charge handle. The M4 probably didn't have 600 rds thru it at the time so I doubt there was any appreciable wear. When I finally replaced the lower with an A2 model I swapped the bolt and handle back and forth for a while but it seemed for the $120 it was worth buying a second bolt and handle and having 2 operational ARs. Both uppers were made by the same company and it didn't appear to be a problem.

I would say at least have a bolt for each barrel, as they will "wear in" to each other.  If money is tight you can reuse the carrier between them.  (And the charging handle too.)

I'd just get two full units though.  Then it's just push the takedown pins to swap them instead of trying to pull the cotter pin & cam pin out at the range and potentially losing them.