Bad Day at the Range - Help needed

[lordjackel]

Had the day off and decide what a great day to bring the new SBR out for a test run.

20 rounds down the pipe...running great, got it dialed in then...poof...squib. It sounded fine but it didn't eject the casing so after manually ejecting it I checked the bore and sure enough its blocked. (I know how to deal with this one)

So I decide its not going to ruin the day so I grab my Rock River AR and as I go to load the first round it won't go into battery. As you can see from the pic the bolt only goes partially forward. Its locked up at this point and only prying with a screwdriver will disengage it. I check the round (factory), bore is clean, don't see any glaring issues, its lubed. Disassemble the upper don't see any issues with the bolt (from what I can see). Put it back together...next round...same thing.

Ideas??


Thanks for your help

 

[1911ly]

Should havve used a barrel instead of a pipe!

Are these reloads? Or the same batch of ammo. If they are you have your common denominator. I hate bad range days!

 

[lordjackel]

Are these reloads? Or the same batch of ammo. If they are you have your common denominator. I hate bad range days!

Factory PMC brass ammo. I have shot probably 500 rounds from this batch with no issues and these rounds were shooting fine in the SBR too till...this is an all the sudden issue that now occurs with all ammo (factory and reloads). I just tried an empty case...and same thing its locked up.

Ideas?

 

[85t5mcss]

Had a similar problem with the bolt before. I pulled it apart, firing pin out and cleaned it all. Put it back together no more issues. Don't recall exactly the problem, but it was firing pin related.

The ammo. ???? Sounds like a squib. Any oil get on them, possibly?

 

[1911ly]

If it is the case sticking in the chamber? Try cleaning the chamber really well. On my .223 I use a .45acp brush. I do it around 500 to a thousand rounds. Probably over kill but I do it. PMC has always shot well for me. Steel Tula I avoid like the plague!

 

[wsenefeld]

Trying to rule out one possibilities. Did you previously run a .22 conversion kit on it and lead the barrel to the point a .223 round would not chamber?

 

[lordjackel]

Had a similar problem with the bolt before. I pulled it apart, firing pin out and cleaned it all. Put it back together no more issues. Don't recall exactly the problem, but it was firing pin related.

Interesting....OK I will tear the bolt apart and see if that is the issue. Thanks for the idea.

 

[lordjackel]

If it is the case sticking in the chamber? Try cleaning the chamber really well. On my .223 I use a .45acp brush. I do it around 500 to a thousand rounds. Probably over kill but I do it. PMC has always shot well for me. Steel Tula I avoid like the plague!

Tried really scrubbing it...this is what I thought just really dirty. Even clean the bolt won't go all the way forward.

 

[lordjackel]

Trying to rule out one possibilities. Did you previously run a .22 conversion kit on it and lead the barrel to the point a .223 round would not chamber?

Nope...never any conversion. I scrubbed the bore and barrel after I got home (ran back to range) but its still doing it.

 

[indykid]

Check around the lugs in the barrel that the bolt locks into. Make sure none are cracked, chipped or otherwise damaged. Make sure there are no tiny pieces of brass stuck in the area that the bolt locks into.

 

[top hat 45]

will the bolt got into lockup without a case/round in it?

 

[Double T]

How hard is it to move the lug on the bolt? Maybe there is debris in their causing it to jam up.

 

[remauto1187]

Yep check the lugs on the bolt and the barrel for damage or buildup.

 

[lordjackel]

Ok update...The bolt WILL lock up without a round chambered.

It will NOT lock up with a live round or even an empty case.

I tried a different bolt and same problem...so seems something with the chamber. I scrubbed it clean. Bore light shows nothing I can see...but when I slide an empty case into the chamber it sticks out about 1/4".

Frustrated as all get out. Other ideas?

 

[1911ly]

There has to be something in the chamber. Have you tried putting a case in the chamber without the bolt? Maybe color the case with a Sharpy and see if you can see if it is rubbing.

 

[top hat 45]

i had a similar situation with a semi auto pistol. ended up being the first 1/4 inch of brass broke off the case. i think you'll have to pull the barrel to see that with a strong light. if you've got a chump case, grind off the end ahead of the taper and see if it will go in.

 

[Mudcat]

An empty or fired case is bigger than a loaded case. When fired they expand and shrink just a little. It is not uncommon for a fired case to not fit into the chamber. That is why we as reloaders will resize (squeeze) the brass to bring it back into spec.
I had a similar problem once with a 5.45x39 AR, it turned out to be the end of a piece of steel not brass stuck in the chamber where it necks down. It was real hard to see but easy to remove. I put the entire upper in the freezer for a few hours then rand a real tight patch from muzzle to breech pulled it right out. I then cleaned the chamber very well and it never did it again in several thousand rounds through it.

 

[lordjackel]

Thanks again for all the ideas...update...

I stripped and cleaned the bolt (just to be sure), as I said earlier I had tried another bolt with the same issue.

For clarity the empty cases I was using to test are fire formed in this rifle so should be a perfect fit...but just to be sure I took a factory round and pulled it apart and tried that case...same issue. (I am a reloader too)

Soooo...into the freezer the upper went...will see in a few hours if it allows anything to be removed from the barrel.

If this doesn't work I will take the barrel off the upper and see what I can see...uggg

Thanks everyone.

 

[parsimonious]

 

[Trigger Time]

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