AR BCG lockup What causes it?

conmaesta

conmaesta

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I've had a few AR's in my day and with a few I've had the problem of the bolt locking up. My suspicion is that it was because the guns were new and the ammo I was using. Both were great quality rifles. The only one I never had this occur with was a Norinco back in the day. With the others I had no problems with the snap caps in .223 and with good factory ammo same thing no problem. But with milsurp ammo every now and then I'd get the lock up when charging the gun. Am I doing something wrong here or is it the rifles. One had a .223 Wylde barrel the other was a .5.56 barrel. I used pretty much just CLP to lube the gun. The rifle I have now, a Colt M4 I use remoil and a light grease on the BCG and have had no issues.
Any ideas?
 
Stuck case tend to be caused by a weak extractor, check your extractor for damage and wiggle it, there shouldn't be a lot of movement or at least not very noticeable
 
A new gun, if built properly, with decent ammo should have zero issues. I've never had to 'break in' a rifle to get reliability, I've always had it from day 1. Can you describe your problem a little more?

Do you mean when a fired round is stuck in the chamber?
 
remoil and a light grease on the BCG

not the best option for lube on an AR. Try Slip 2000 EWL, Rand CLP or Weapon Shield CLP. don't be afraid to lube. AR's will run dirty, but not dry, they need lube.

Boltgun
 
OP,
You say you get “ lock up” when charging the gun. I’m assuming you mean loading the first round off the mag?
I’ve seen this problem occasionally if you load off a full 10rd or, in the old days, a Beuwolf mag with a closed bolt. If the mag isn’t pinned or crimped properly, the pressure of the full mag pushing on the underside of the BCG may feel like a jam or “ lock up”.

Try downloading your mags and see if the problem happens.

The only other time I’ve seen something like a BCG jam is either with overcharged ammo/ case over expansion or a poorly lubed carrier.

Since you say you lube your gun and this problem happens when “ charging” the gun, then I doubt the above are your issues. I would check your mags then eliminate the mag that has the issue.
 
First off the mags aren't the problem at least with the last rifle, I was using pmags which are great. What I meant by charging the rifle is load a magazine, insert, bring back the charging handle and let go to rack the first cartridge. Then the bolt doesn't fully engage into the chamber and if you fire of course there is a click and nothing, try pulling back the charging handle and it is stuck. Have to mortar it to get the bolt unstuck..I have read all of the fixes to get it unstuck, I want to know what you all know about why it happens...I think its my ammo which was milsurp stuff however both rifles were as I said either .223 Wylde barrels or 5.56 barrels. Also no issues with snap caps in .223 or .223 factory ammo. Hope I've explained it a little better.
 
Considering you have no issues with factory 223 ammo/ snap caps, I think you've narrowed down the problem to ammo. Stupid question but you say it's "surplus" 556......are you that's exactly what it is and isn't actually a different caliber?
 
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So, the ammo is Wartak 223 remanufactured ammo 55 grains. As far as trying from an open bolt no I haven't tried that but it sounds like a good idea. The rifle I was having the issue with is a Diamondback. I have subsequently taken it apart essentially. I'm going to buy a new upper for it and put it all back together and see what happens. My Colt M4 has no issues and I have a build that I put together with no issues. But that DB was awful.
 
conmaesta said:
So, the ammo is Wartak 223 remanufactured ammo 55 grains. As far as trying from an open bolt no I haven't tried that but it sounds like a good idea. The rifle I was having the issue with is a Diamondback. I have subsequently taken it apart essentially. I'm going to buy a new upper for it and put it all back together and see what happens. My Colt M4 has no issues and I have a build that I put together with no issues. But that DB was awful.
Click to expand...


Well, there's your problem.

Wartak makes Tula look like match ammo.
 
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