Ar build issues

Decided to start a new thread( not sure if that’s proper etiquette, if not sorry)

So my upper came

in from bca, 223 wylde, put everything together, went outside to check function. Loaded a primate rollermag with Hornady black .223 62 gr. Fired the first round no problem, round ejected, pulled trigger and nothing. Pulled charging handle to rear and it wouldn’t move. Had to disassemble and gently pry bcg loose. Loaded a single round, and fired with no issues. Noticed marks on round that were not there before. Any help would be appreciated
 
Did you assemble upper or did bca? If they did I would call them for suggestions.

You said it ejected, but did it load the second round? Or did the bolt lock back
 
BCA assembled upper. It chambered the second round but when I had fail to fire, I pulled charging handle and bolt carrier would not move. I’m trying to rule out any possible issues on my end
 

Mr.Gadget

Old Mossy Horns
Hard to see but I would say something with the mag and jump to barrel extension.

Always test as close to as you can known parts. No sure about your mag. New guns with full mags can be very problematic.
I use usgi mags for testing and only load on round at a time in the mag. Use 5 mags then set down with new round and 5 shot rounds look them over and measure to check head space.

Reason I do one round. It is bad enough if something goes south. Having had guns blow up or out of battery fire I learned.
So try USGI or magpul with one round then 3 to 5 per mag and see.
That is what I would do.
Could just be be mag or ammo.
 

Mr.Gadget

Old Mossy Horns
BTW did you clean and lube? I run new guns wet. They tend to have a lot of grit to the finish.
I lube everything, buffer, spring and full BCG and lugs.
 
Mr. Gadget, I believe you hit the nail on the head

Loaded one round directly into chamber, no mag, fired fine

Loaded three rounds in mag, closed bolt, fired first shot, no go on second shot, bolt stuck( no go on 2 different mags)

Loaded one round directly into chamber, then inserted mag with 3 rounds under closed bolt, fired all 4 rounds no issues

And yes sir, cleaned bcg, star chamber and interior upper receiver with solvent and relubed with clp
 

Mr.Gadget

Old Mossy Horns
Please be careful loading rounds direct to chamber. Taking a round from the mag has drag on the BCG if you drop a round in chamber the BCG closes full force. It can slam fire. These and others have floating pin. It can have the speed and mass to set of some types of ammo.
To show what I'm talking about, at a safe place at the range load one round into chamber BCG to the back locked. Tap the bolt catch and let it slap home full force. Remove the round and check the primer. I do this on all my guns to see how it responded. Easy way to see what it will and will not do. It also is a easy way to see with you eyes if the FP is too long by looks.
Remember be safe. I have got calls from people that have shot car and inside their house due to slam fire.
 
Sorry, should’ve specified, I rode the bolt closed, learned about slam fires the hard way at Bragg one day, soldier had an ftf and loaded his last round by hand instead of putting it back in the mag, hit the bolt release before range officer called for alibi fires. Luckily he was at least pointing down range when it went off but he got an earful from that range officer.
 

Mr.Gadget

Old Mossy Horns
10-4 I was betting on that so more for anyone tuning in that may be misunderstanding what is being talked about.
 
Gotcha, Appreciate all the help from yourself and sclowcountry , bca usually shows a three round test group on there website from the uppers they sell, not that issues don’t happen but wanted to check everything on my end first. I’ll have to grab some pmags for zeroing this weekend
 

pattersonj11

Old Mossy Horns
Please be careful loading rounds direct to chamber. Taking a round from the mag has drag on the BCG if you drop a round in chamber the BCG closes full force. It can slam fire. These and others have floating pin. It can have the speed and mass to set of some types of ammo.
To show what I'm talking about, at a safe place at the range load one round into chamber BCG to the back locked. Tap the bolt catch and let it slap home full force. Remove the round and check the primer. I do this on all my guns to see how it responded. Easy way to see what it will and will not do. It also is a easy way to see with you eyes if the FP is too long by looks.
Remember be safe. I have got calls from people that have shot car and inside their house due to slam fire.

This may answer a question I have had. I have loaded direct from magazine, but did notice over the years a round or two that had an light intention in the primer. I guess it can happen coming from the mag. I don’t know that I have ever dropped one into the chamber on an AR.
 

Mr.Gadget

Old Mossy Horns
This may answer a question I have had. I have loaded direct from magazine, but did notice over the years a round or two that had an light intention in the primer. I guess it can happen coming from the mag. I don’t know that I have ever dropped one into the chamber on an AR.
Yep
Tends to show more when it is in the chamber and BCG dropped.
Second when low round count in mag and BCG dropped.

Just think about the different degrees of no pressure light pressure to most pressure full mag. That on the bottom of the bolt.

Most guns with floating FP do it. M1, M1A, carbine, AR, AK.......
 
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