Last month I purchased a brand new Bushmaster M4A1 from a shady local dealer. I was so excited I couldn't put it into words. I got home and showed some pics, only to discover some people on here thought it might be a gun that was pieced together from other parts. I called Bushmaster and they confirmed that my barrel, upper, lower and stock was all shipped from their factory exactly the way I received them. That was a huge relief!


As it turns out, it looks as though my gun was at a gun show at one point. I know, I know, that's bad, but we do know the barrel, upper, lower and stock came from Bushmaster exactly the way they are now. The only parts I am paranoid about are the bolt carrier group. As many on here say, those are the most common parts to be swapped out with crappy parts.

Well, I thought maybe some of you could help me figure out is mine are the ones that came from Bushmaster, or at least the quality that they would use. I honestly have no idea how to tell.

Here are some pics. Thanks to anyone who can help me out with this.

i honestly dont know if anyone can determine the manufacture/distributor of a particular B/BCG...

but i compared your bolt to my Bushy (origional owner, origional parts, bought NIB 2003) and there are some difference:
your end of the BC has a little more metal/length present (where the notch is at); your stake keys are definitve hex heads--mine are a little smoother and have "YFS" marked on em; your finish is a little more matte and lighter shaded (But yours might just need some CLP)
rest of it looks like about any other of my BCGs...

I have you fired this weapon yet?

Because if you haven't, the Bolt and Carrier look used to me

But on the other side, at least you have a nice full circle carrier and the gas key is staked.

I dont know which bolt carriers Bushmasters are shipped with, I'm sorry I couldn't be more helpful

Quoted: I have you fired this weapon yet? Because if you haven't, the Bolt and Carrier look used to me But on the other side, at least you have a nice full circle carrier and the gas key is staked. I dont know which bolt carriers Bushmasters are shipped with, I'm sorry I couldn't be more helpful

Yeah, this BC has roughly 700rds through it.

Is it possible to tell if this one is high quality or complete junk? The reason I ask, if I try and test it myself, it would be more expensive to cycle a couple thousand rounds through it than it would to just buy a whole new unit. I don't have fun testing weapons.

No reliability problems once I switched to good magazines. The problems I had before was hang-ups on the feed ramp. It happened maybe 3-4 times all with the same magazine.

Quoted: your finish is a little more matte and lighter shaded

I completely cleaned mine with gun scrubber before taking the pics.

I don't know which part you are referring to being different. Maybe someonecan help me understand.

I have seen many new Bushmaster rifles with that bolt carrier group. However, since Bushmaster does not mark their bolts it is not possible to track down the manufacturer of the bolt. But I have seen that style carrier in New Bushmaster rifles before. The carrier key appears to be very poorly staked.

Quoted: I have seen many new Bushmaster rifles with that bolt carrier group. However, since Bushmaster does not mark their bolts it is not possible to track down the manufacturer of the bolt. But I have seen that style carrier in New Bushmaster rifles before. The carrier key appears to be very poorly staked.

When you say it is poorly staked, what does that mean? Should I buy a replacement if I demand good quality?

Clean it with CLP and a brush to get that carbon off.  Gun Scrubber does nothing to get carbon off.  It is a degreaser.  

It looks just like my bushy BCG...  Yes, the staking is weak.  Not a big deal, just look for the thread on staking and do it yourself.  Easy fix.  

I wouldn't worry about the QC issue.  Bushy doesn't MP test anyway so even if it is CMT, LMT, etc, you have about the same thing.

That b and b/c look fine. Clean, lube and have fun. Don't sweat it.

Quoted: That b and b/c look fine. Clean, lube and have fun. Don't sweat it.

Yup.  I'm not seeing anything in those pics that would cause the slightest amount of concern, Cleatus!

Quoted: Quoted: I have seen many new Bushmaster rifles with that bolt carrier group. However, since Bushmaster does not mark their bolts it is not possible to track down the manufacturer of the bolt. But I have seen that style carrier in New Bushmaster rifles before. The carrier key appears to be very poorly staked. When you say it is poorly staked, what does that mean? Should I buy a replacement if I demand good quality?

It just stops the bolts from backing out.  As said above, you can easily do it yourself.

See the little indents/dimples on opposite ends of the carrier key bolts?  That looks REALLY week and doesn't look like it would do much.  They should go into the bolts a little more.

It looks like the BCG from my Bushmaster with the only exception being the hex head bolts on the carrier key.  

+1 on the carrier key stakes (the indentions on the carrier key that "pinch" the carrier key bolts).  They look good on the left side, but the right side stakes don't appear to make contact.

Good luck and happy shooting.

it has the shrouded firing pin which is common to newer colt, bushmaster and RRA so its at least a quality carrier if every thing else was bushmaster then good chance its also a bushmaster.  btw a lot of bushmaster parts are not made from them they source out some of their parts like some of the other manufatures not sure which parts.

Quoted: Is it possible to tell if this one is high quality or complete junk? No reliability problems once I switched to good magazines. The problems I had before was hang-ups on the feed ramp. It happened maybe 3-4 times all with the same magazine.

Where on earth did you get the idea that bolt carriers are a commonly junk shop produced part?

Or for that matter, bolts?

True, DPMS had a run of bolts that were probably over hardened, and started cracking , but that was years ago.

Your bolt and carrier look  fine, and are almost certainly original, but even if they aren't, so bloody what? You've already established that they're functional  

Friend, if you're as big a worrier about life in general as you seem to be about these parts, I predict early ulcers