I've got a couple of AR issues that are new to me.

[Vigilant]

From your pictures, it does appear that there may be uneven wear on the receiver extension/buffer tube, but that can be applied to the “wiggle” you self diagnosed. Or you could have an out of spec receiver OR, receive extension(buffer tube)? Where are you located? Do you have a current 23&P, if you are Indy local-ish we can bump elbows and look?

 

[BGDave]

While you have the bolt out, check and see if you don't have really sharp bolt lugs (meaning the front and back edges). Various bolt manufacturers use different methods to break the sharp edges. Compare it to your other bolt and carrier group that seems to work well.

On another note, that upper looks like it could use a good cleaning. No offense. Good luck with your rifle.

 

[teddy12b]

I'm not sure what a 23&P is. I've never heard of it.

The lugs on the bolt are noticeable sharper then most.

Yeah the whole gun is completely filthy. I pumped a lot of wolf through it to break it in.

 

[Vigilant]

I'm not sure what a 23&P is. I've never heard of it.

The lugs on the bolt are noticeable sharper then most.

Yeah the whole gun is completely filthy. I pumped a lot of wolf through it to break it in.

23&P is the tech manual regarding everything AR/M4/M16 it’s the build specs and parts/repair manual. TM 9-1005-319-23&P

 

[Hohn]

For starters, the “stock”/lower receiver extension” should NOT be at all loose. No amount of “wiggle” is good. The 23&P has SPECIFIC torque values, for even the receiver extension. Then, the castle nut should be staked to eliminate any “wiggle” left. It also has a specific torque value. There should be NO “wiggle”, even with a nonstandard/non milspec stock system.

These days I skip staking in favor of purple loctite. Works great, easier to service.

 

[Vigilant]

These days I skip staking in favor of purple loctite. Works great, easier to service.

I still stake, but you are correct that thread locker will work, the point is, ANY wiggle is too much, and will eventually cause problems.

 

[churchmouse]

I'm not sure what a 23&P is. I've never heard of it.

The lugs on the bolt are noticeable sharper then most.

Yeah the whole gun is completely filthy. I pumped a lot of wolf through it to break it in.

Not sure how running crap dirty ammo will break anything in...….

 

[TJ Kackowski]

Not sure how running crap dirty ammo will break anything in...….

The sludge acts as a polishing/grinding compound to more quickly mate surfaces ... or so I'm told

 

[teddy12b]

I apologize for the delay, but today I was able to swap out the Bolt Catch. I went out back with 2 30rd pmags full of wolf 223 55gr fmj and one okay E2 mag full of XM193.

Everything shot and cycled 100% and I should be grateful for that. The wolf ammo ejected to my right and behind me. I'd say 90 degrees plus. The XM193, recoil felt much more stout and again the ammo ejected almost directly in front of me and to the right exactly how it had before.

The new bolt catch is showing some same signs of being hit by the BCG.

The new bolt catch will also catch the BCG on the actual bolt carrier group body as before. Basically every issue I was having before, I'm still having.

My next move will likely be swapping the upper and lower and seeing what happens then.

Any suggestions are welcome.

 

[Hohn]

Your swap of upper/lower sure seem to suggest the problem is in the upper. As you indicated, the upper on another lower still has a problem, while a different upper on this lower works fine.

So that said, I would start looking into possible machining errors on the upper.

 

[1mil-high]

I would move toward the gas system or buffer now assuming you changed the spring and plunger for the bolt catch as well. What weight buffer are you running currently?

 

[teddy12b]

The other night I took this rifle out again, along with my old trusty 6920. I swapped the uppers and ran some XM193 out of each. The problem is with the upper, and at this point I'm going to send it back to PSA.

 

[teddy12b]

Its been a while, but tonight the MOE stock kit arrived from PSA. Replaced the buffer tuber, spring and buffer with the new one. Ran 3 mags for 90rds and they about all ejected around 90 degrees to the right. It felt smooth like any other AR. I guess it was just that RRA entry stock kit.