Help! Ejection issue after chambering live round

[!Nvasi0n]

So a friend of mine insisted I build him a 7.62x39 AR from parts he had. Not sure of barrel brand or twist, but I do know it's a red X brand bolt and carrier as it was new in package.

Here's the problem, after assembling the gun, I can take a round drop it in the chamber release the bolt, and fire, and get solid ejection. I can also insert a fresh magazine (7.62x39 ar mag) chamber a round and fire until empty with no problems.

However, it's his hog hunting gun, and after hunting..when he tries to eject the live round from the chamber...it's stuck tighter than bark on a beech tree. I can stomp the round out though, or wedge the charging handle against a tree or table and push hard and eject the round.

I just can't manually eject it... I'm guessing it's taking upwards of 40-80 pounds of force to eject.

I can cycle the bolt manually, and feel some resistance, but it still locks up and opens with just a little more than normal force.

Any ideas what's going on here?

[SkipD]

First off, you are not referring to an ejection problem. You are referring to an extraction problem. They are VERY different.

What ammunition is being used? The first thing I would do is use a gauge to determine whether or not the ammunition is the proper size so it can fit properly in a standard chamber.

Next, assuming the ammo used is properly sized (checked with a calibrated gauge), I'd make sure the chamber is truly clean and then see if the same problem exists. The ammo could have a coating on it which adheres to the chamber and makes newly charged rounds stick tight in the chamber.

[!Nvasi0n]

Thank you for the correction. The ammo used at first was wolf, followed by commercial hunting ammo with brass cases. The barrel was cleaned prior to assembly, after firing the wolf, and multiple times since the switch to brass cased hunting ammo.

A chamber brush was used, along with both Hoppes or foaming bore cleaner.

I used a field go no go gage and everything is fine barrel wise.

I'm leaning towards a bent or misaligned gas tube.

[SkipD]

I'm leaning towards a bent or misaligned gas tube.

If I'm understanding your idea properly, you'd have a problem manually opening the bolt with nothing in the chamber if that were true.

Buy or borrow a cartridge case gauge (any well-equipped handloader should have one in my opinion) and check the cartridges you've been using (prior to firing them, of course).

Even if the chamber passes all three headspace gauge tests (go, no-go, and field), the throat could be tight. Headspace gauges don't reach into the chamber's throat or leade areas.

[Hill_Country556]

Thank you for the correction. The ammo used at first was wolf, followed by commercial hunting ammo with brass cases. The barrel was cleaned prior to assembly, after firing the wolf, and multiple times since the switch to brass cased hunting ammo.

A chamber brush was used, along with both Hoppes or foaming bore cleaner.

I was going to say that the chamber was extra dirty from the steel cased ammo (Wolf) and then firing of the brass cased rounds in said extra dirty chamber caused them to be sticky but you say you cleaned it real well...

I agree that a misaligned gas tube would cause the bcg to be hard to cycle even with an empty chamber. It would almost HAVE to be out of spec chamber and/or ammo, right? Unless you have a tiny piece of debris of some sort in the receiver extension that's binding the buffer/spring up. Hard to imagine that though...

Bolt is binding up in the barrel extension somehow? Something is out of spec in that area?

[Iraqgunz]

I wouldn't be surprised if the chamber is out of spec.

[Leaveammoforme]

Is it common for x39 chambers to vary or be out of spec in AR style barrels? I know barrel is of unknown orgin, so maybe it's a cheap? Or, is your response just based on OPs description of failure?

I wouldn't be surprised if the chamber is out of spec.

ue

[Iraqgunz]

I have seen this before with these barrels. Even more suspicious is "No Name Arms Manufacturing". It could also be that there is some misalignment of the barrel extension, and the bolt lugs are dragging against the locking lugs in the barrel extension. Of course, this is also guess since we have no idea about some of these components. From what I have seen of the Red X Arms 5.56 BCG's I am less than impressed.

Is it common for x39 chambers to vary or be out of spec in AR style barrels? I know barrel is of unknown orgin, so maybe it's a cheap? Or, is your response just based on OPs description of failure?

ue

[!Nvasi0n]

IG, I'm inclined to agree with you on two points. First, out of spec chamber which a smith ought to be able to remedy with a chamber reamer and gages. The second point is the barrel extension alignment. Since I don't have fancy concentricity Gages, or two indicators and Vee blocks, I'm thinking I may be able to put a little layout die on the bolt lugs, and manually cycle the bolt. If there is interference, theoretically on one or more of the lugs it should wipe off some of the layout dye.

Thanks all.

[duckspeaker1]

Are there witness marks or scratches on the casings after firing? that could eliminate or pin point a potential issue right there....