Jamming Issue, need some pointers

[FirstARinNY]

Thanks gunut, Hoot and Billy the Kid for all the great input. I'm gonna have to rule out mag problems for now cause shooting single shot (no mag) causes stove pipes. I think i'm gonna take the runt to a gunsmith cause I've called Bushmaster multiple times and had very odd conversations about when I would get the upper back. Seems like when they moved locations they forgot their brains. I trully appreciate the help here and will post when I hear anything. Need this F@#$!%ing for deer season-time's awaistin!!! - Thanks all- Jim

[Hoot]

...snip...I'm gonna have to rule out mag problems for now cause shooting single shot (no mag) causes stove pipes...snip...

That's a horse of a different color. Check your ejector plunger to make sure it'll flip an empty with authority and it doesn't feel crunchy as it depresses. The easiest way is to remove the BCA, hook a case under the extractor hook, pull the empty into the seated position and release it, letting it fly.

Lately, I've read of folks with other caliber ARs, discovering brass shavings down in the plunger hole causing it to bind. Otherwise, if you have a caliper, measure the ejection port opening to make sure it was machined wide enough to clear the brass. Pass along the dimension and I'll measure mine to compare.

Hoot

[wildcatter]

...snip...I'm gonna have to rule out mag problems for now cause shooting single shot (no mag) causes stove pipes...snip...

That's a horse of a different color. Check your ejector plunger to make sure it'll flip an empty with authority and it doesn't feel crunchy as it depresses. The easiest way is to remove the BCA, hook a case under the extractor hook, pull the empty into the seated position and release it, letting it fly.

Lately, I've read of folks with other caliber ARs, discovering brass shavings down in the plunger hole causing it to bind. Otherwise, if you have a caliper, measure the ejection port opening to make sure it was machined wide enough to clear the brass. Pass along the dimension and I'll measure mine to compare.

Hoot

Hoot may be unto something here, I just recently had this very problem and cured it by removing the chunk of brass that was clogging the ejector hole..

..t

[DFWDave]

I know this is an old thread, and likely the OP got his problem fixed and just didn't update the thread to describe the solution, but I had this exact problem with my Bushmaster XM-15. Every single round was an FTE just as described. The spent case was hanging halfway out the ejector port. It was a single-shot rifle for 120 rounds. I thought by that time the rifle should be broken in and I should not be seeing FTEs.

I did the unthinkable: I called Bushmaster. The customer service guy there suggested I check the 3 gas rings at the back of the bolt. I thought that was a brilliant idea and ran home to make sure they were spaced at 120 degrees all the way around. Unfortunately they were pretty close to 120 degrees, so I just moved one of them a hair to make it precisely 120 degrees just in case.

Then I remembered what the rep had said: if the rings aren't spaced right, the gas will blow by them and the bolt won't run all the way. I started thinking about the fact that whenever I cycle the operating handle, it seems the bolt returns forward kind of sluggishly. I wondered whether maybe there was some friction somewhere causing the bolt not to slam back and forth with sufficient force to do a proper ejection. So I tore the gun apart, cleaned it all, and paid special attention to the lubrication instructions. Where to lubricate heavily, where to lubricate lightly. And I removed the buffer spring from the tube in the stock and lubricated that as well. I had never done that, and voila, now the bolt seems to run much faster when I cycle the handle. And sure enough, when I took it out to the range, every single shot was a perfect ejection. I fired 60 rounds and called it CURED!

Make sure the bolt can fly back and forth without friction.

[Siringo]

Lubrication is 99% of problems or lack of. Ring spacing is a myth. Those things move around anyway during firing --- remember the bolt is rotating during this cycling process and those rings are not fixed in position.

[Colohunter]

After shooting a lot, check your rings again, they won't stay in position, it doesn't matter. They are compressed once the bolt is put in the carrier anyway. Make sure you lube! At my department I've seen a number of people thinking that their rifle needs to be run dry, and they seem to be the only people that have function issues.

The link seems to be dead now, but there was an article in SWAT magazine about Pat Rogers using a 14 inch carbine for his classes with minimal maintenance, but lots of lube. Last update I saw on ARFCOM was that it was up over 40,000 rounds.

[Jim in Houston]

Sometimes it's difficult to tell a failure to extract from a failure to feed or eject. My limited experience with the 5.56 was a weak extractor spring. Brownells sells a heavy duty one, which I installed in the bolt, and that solved my problem. However, the symptom I experienced was that the spent cartridge was only partly pulled back out of the chamber and the next round had fed up underneath it, jamming both. The stove-pipe situation probably means a lube problem as discussed in other posts. I have been told to keep the bolt heavily lubed, and that if I experienced problems during firing to just lube the bolt with some gun oil and keep on going.

[Colohunter]

Jim, lube can definitely help. What you explained sounds like a failure to extract. If the empty is still in the chamber fully, or partially it is possibly the extractor. If it is removed from the chamber, but doesn't get ejected from the action, then it is more likely the ejector.

The extractor is easy to remove and I remove my extractor every time I disassemble the bolt carrier for cleaning. The ejector is harder to remove without the proper tools and I only do that every so often. One way to check your ejector is to try and push it down using your finger nail. Most of the new ejector springs make it very difficult to depress, whereas some of the worn out springs have let me push the ejector flush with the bolt face fairly easily.

[Texas Sheepdawg]

My Thumper stovepiped once. I wanted to single fire one round so I took the round and hand loaded it in the chamber, but did not have my mag installed. When I fired, it stove-piped. I think since the magazine wasn't there, the bolt catch did not engage the carrier so it was just a fluke. I haven't had any problems otherwise.

[Jim in Houston]

Thanks for the correction Colohunter! Yes, I meant to say extractor. I have edited the original post and replaced ejector and eject with extractor and extract.