Bolt stuck in BCG

[akjunkie]

This past 2 months I've taken my M4 to the range 3 times.
My AR wears a Bushmaster M4 upper. Bought it back in 99.

After each range trip I would clean my rifle.
Each time the Bolt is stuck in the BCG.

1st time: Couldn't pull the charging handle back. Had to tap it out with a rubber mallet. Once the BCG was out, the bolt was stuck inside. Bolt wouldnt rotate freely. I just assumed, I shot alot of rounds and didnt properly Lube the BCG innards.

2nd time: Was able to pull the charging handle back. Removed BCG and same thing. Bolt was stuck inside BCG. Had to tap it with a screwdriver handle to make it move.

3rd time: Went shooting this morning. I did a detail Strip and Lube last nite.
Shot 200rds today. Same thing. Bolt stuck in BCG. This time, Bolt was still dripping wet with gun oil.

Only thing i could think of that is causing my bolt to stick is the bolt rings.
My upper is 12yrs old and got at least 5000+ rds thru it.

I removed the original bolt ring. ( to my surprise, it is a One piece ring)
Installed new 3 piece ring from my spare parts kit.

Do my fellow Calgunners think I fixed the "sticking" problem with new Rings?

My bolt doesnt slide in and out as freely as before, but I assume that's becuz I need to break in the new rings.

I have a 8hr carbine class this coming Sun the 13th. Dont have time to hit the range again before the carbine course to test fire my rifle.

In case I didnt fix the problem. I'm thinking about bringing a spare/used BCG off another AR. Would there be a headspace problem involved?

[G-forceJunkie]

The only time I have seen bolts really stuck in carriers is when they are filthy dirty. As in have to chip the stuff out. Clean the heck out of your carrier (way down inside, scrape all the hard carbon out) and scrape all the carbon off the tail of the bolt. Scrape the hole in the carrier when where the tail of the bolt goes inside when its locked up. Take the rings off, and reassemble the bolt with the cam key. It should not bind at all. If it does, something is mechanically wrong or bent or warped. After that many rounds, that bolt ought to be loose enough you can just hold the carrier and "fling" the bolt forward with a quick whip of your wrist.

[wisefire]

Had a similar problem, bolt was tight in the bcg, shoot about 50 rds and notice charging handle was stuck. Took some force to get it free and more force to get the bolt out. All this happen even with good amount of lube. Changed out the rings and never had the problem again

[vintagearms]

Change out the rings. If that doesn't do it, buy a new BCG.

[JagerTroop]

After you remove the bolt from the carrier, clean it, lube it, does it go in smoothly? Can you whip it forward (as G-force stated)?

If it goes in hard it may be excessive carbon fouling, marred/galled contact points, maybe a burr. Heck, maybe the tail section of your bolt is bent. Bolts don't last forever.

If you use a different carrier, the headspace should be fine. The headspacing is set by the barrel extension-to-barrel adjustment. If the bolt is in spec (99.9% of the time they are) you'll be just fine.

When rifles are assembled at the factory, they just grab a BCG from a big bin and toss it in.
If it still concerns you, you should have enough time to order a headspace gauge. A field gauge should be fine, but to really be sure you'll want Go and No Go gauges.

Just to reiterate; I would just grab a new BCG and slap it in. You'll be fine.

[h0use]

Froglube your BCG

[akjunkie]

After you remove the bolt from the carrier, clean it, lube it, does it go in smoothly? Can you whip it forward (as G-force stated)?

If it goes in hard it may be excessive carbon fouling, marred/galled contact points, maybe a burr. Heck, maybe the tail section of your bolt is bent. Bolts don't last forever.

If you use a different carrier, the headspace should be fine. The headspacing is set by the barrel extension-to-barrel adjustment. If the bolt is in spec (99.9% of the time they are) you'll be just fine.

When rifles are assembled at the factory, they just grab a BCG from a big bin and toss it in.
If it still concerns you, you should have enough time to order a headspace gauge. A field gauge should be fine, but to really be sure you'll want Go and No Go gauges.

Just to reiterate; I would just grab a new BCG and slap it in. You'll be fine.

Yes, the Bolt went in nice and smooth after I cleaned and lubed it.
I also did the "Whipping Action" as G-Force stated and the Bolt shot out like it usually does.

Replaced my original (1 piece ring) for a 3 piece.
Also did a very extensive/detailed cleaning of my Carrier in and out, plus scraped off all the carbon off my Bolt "tail".

What do U guys think of these 2 BCGs. Seems affordable enuff.

http://www.surplusammo.com/products/SA%26A-AR15-Complete-Bolt-Carrier-Group%252d-.223%7B47%7D5.56.html

http://www.surplusammo.com/rock-river-arms-complete-ar-15-bolt-carrier-group-223-5-56/

[biglou]

I'd get the M16 bolt (the first one). But if yours is working after you changed the gas rings and a good cleaning why buy one ? Buy ammo

[Nathan Krynn]

The only time I have seen bolts really stuck in carriers is when they are filthy dirty. As in have to chip the stuff out. Clean the heck out of your carrier (way down inside, scrape all the hard carbon out) and scrape all the carbon off the tail of the bolt. Scrape the hole in the carrier when where the tail of the bolt goes inside when its locked up. Take the rings off, and reassemble the bolt with the cam key. It should not bind at all. If it does, something is mechanically wrong or bent or warped. After that many rounds, that bolt ought to be loose enough you can just hold the carrier and "fling" the bolt forward with a quick whip of your wrist.

This is great advice.

Have you ever cleaned out the carrier where the bolt tail goes? I use the CRT for that and it works great.

[akjunkie]

Well, went to the Carbine course yesterday. Ran about 400rds and only had 3 hiccups.

Went home and the bolt was still rotating free in the Carrier.

The hiccups I am talking about are FTFs. The rounds would go 1/2 or 3/4 of the way into the chamber. Each time I remedied the situation by Banging on the bottom of my mags.

I'm assuming the Rings need some time to "break in".

Also ordered a spare BCG from Young Machines (calguns group buy). Guess i'll save that for a rainy day.