View Full Version : Stovepiping jam on AR15
What is the most common cause of a stovepipe jam on a AR15 ??
My first thought would be the ejector. Can you tell us more? Ammo fired, weapon type, etc....
What is the most common cause of a stovepipe jam on a AR15 ??
Failure2Stop
08-01-10, 11:29
In every instance I have seen, it has been due to an ejector issue, unless somehing is semi-blocking the ejection port.
My first thought would be the ejector. Can you tell us more? Ammo fired, weapon type, etc....
First of all, I'm very sorry if I made a mistake here, I dont know what is the problem, should I called it :
1. Stovepipes
2. Failure to Extract
3. Failure to Feed or
4 Short Stroking
I have a year old 16" RRA carbine-length. She was purchased new as a complete uppers. She's seen 500 - 1000 rounds in her life (all PMC or American Eagle or Winchester).
Everything was oiled and cleaned including gas tube before the match. Has H buffer and Mil Spec buffer tube I'm running the donut on the extractor spring, completed chrome BCG.
30 rounds of Winchester Q3131 55gr using Magpul magazine ----------------- 7 Stovepipes
30 rounds of AE 55gr using C Product magazine ------------------------ 6 Stovepipes
30 rounds of PMC 55gr using Magpul magazine ------------------------ 6 Stovepipes
Should I called this a stovepipes problems or ???????
live round loaded in chamber and spent casing stuck behind that live round and the bolt, not fully extracted from the chamber.
Any ideas to what the problem is?
http://i57.photobucket.com/albums/g225/glockstan/Misc/IMG_3510.jpg
http://i57.photobucket.com/albums/g225/glockstan/Misc/IMG_3512.jpg
Grease Monkey
08-01-10, 20:28
Well that's definately NOT a stovepipe!!
decodeddiesel
08-01-10, 20:39
That is absolutely an ejector issue. Check to see if there are brass shaving on your bolt face and in the star chamber. More than likely a brass chip has worked it's way into the ejector tunnel. To fix the issue, you will want to try dripping a good deal of lube in the ejector, then working it in and out with a brass punch until the culprit (likely a brass chip) works it's way out.
This very thing happened in my LMT when I was using a black insert and an O-ring. Basically there was WAY too much extractor tension and when the extractor would ride over the rim of a brass case it would shave away bits of brass. Eventually one found it's way into the ejector tunnel. The whole thing has spoiled me on the O-ring under the extractor "fix"
Failure2Stop
08-01-10, 21:06
Your ejector and extractor strength are out of balance.
What you are seeing is a failure to eject inline double feed.
Try popping the o-ring out and just run it with the extractor spring and clean and lube the ejector.
I would venture to say that you are correct. The extractor tension is either too much and not grabbing the rim or it is too little and slipping off. Also, the ejector seems to not be working properly. If you feel comfortable doing it, disassemble the ejector, clean it and replace the ejector spring. Then install a new roll pin.
Your ejector and extractor strength are out of balance.
What you are seeing is a failure to eject inline double feed.
Try popping the o-ring out and just run it with the extractor spring and clean and lube the ejector.
What you are seeing is a failure to eject inline double feed.
So that empty casing is pushing a live round into the chamber, right?
I kind of wondered about that. I was looking at the pic real closely and it almost looks as if the primer on the round in the chamber has been struck. Or it's an optical illusion.
So that empty casing is pushing a live round into the chamber, right?
Yeah, or a light strike from the spent case, perhaps? I don't see any logical way for the one in the chamber to be spent, too, but....
Yeah, or a light strike from the spent case, perhaps? I don't see any logical way for the one in the chamber to be spent, too, but....
Failure of the extractor maybe?
I don't see how this situation can even happen. The BCG would have to stroke back the additional length of the spent casing,without ejecting it, in order for the spent casing to push the next round into the chamber. Obviously something is going terribly wrong here. I just have a hard time wrapping my brain around what it could possibly be. Unless the BCG failed to extract the chambered round, then slammed the next round into the still chambered round hard enough to ram the bullet of the next round down the neck of the case. Aside from that scenario I have no way to explain what I see in this picture. Someone please help me understand what I am seeing here. :confused:
Vince
So that empty casing is pushing a live round into the chamber, right?
How on earth does that happen?
I don't see how this situation can even happen. The BCG would have to stroke back the additional length of the spent casing,without ejecting it, in order for the spent casing to push the next round into the chamber. Obviously something is going terribly wrong here. I just have a hard time wrapping my brain around what it could possibly be. Unless the BCG failed to extract the chambered round, then slammed the next round into the still chambered round hard enough to ram the bullet of the next round down the neck of the case. Aside from that scenario I have no way to explain what I see in this picture. Someone please help me understand what I am seeing here. :confused:
Vince
I'm with EW.
I don't see how this can occur during the cycle of operation.
Even with the extractor compressed and stuck in place. During the chambering cycle, the spent shell casing would be forced upward and jammed into the barrel extention. The live round would not be able to chamber and forced down hitting the lower portion of the barrel extention. This is what most people refer to as a double feed.
In my feeble mind, I can't phathom how this could possibly happen.
If someone figures this one out please let me know how it was done.
It looks as if the primer on the chambered round has been struck.
The case inline with the chambered looks as if its been fired and is empty.
Even if the chambered round is live, and empty round being lodged behind a fully chambered round is not plausible. I have seen empty cases become lodged over the gas tube and partly feed the next round, but this?
Does not seem to be mechanically possible.
I decided this due to the fact that even if the spent case was extracted from the chamber, but was not ejected from the weapon, how would the bolt strip a new round? Unless, the spent case was pitching at a downward angle as the action cycled? However, that is not possible as the BCG will not travel rearward enough for this to happen.
Only possible scenario would be as EW1066/Vince said, the "spent case" was not a spent case. The bullet was pushed back into the cartridge... Which would explain the appearance of a primer strike on the chambered round. But, I believe there would have to be quite a bit of force excreted on the cartridge to set the bullet back that far.
So I did a little test.
I took a spent case and lightly crimped a 55gr bullet in an unsized case. I loaded that case at the top of a full mag. I locked the bolt back and inserted a spent case in the chamber. Then, the magazine with the lightly crimped bullet was inserted into the firearm. I then proceeded to close the bolt using the bolt release. The bullet set back into the body of the cartridge, wedging against the chambered round and between the right lower bolt lug (looking at the weapon from the rear). The case that was stripped and lodged in the action just clears the feed lips on the magazine. So, with all of the forces going on in the weapon during live fire, it is possible that the case would have jumped up and become level if there was some sort of bounce when the action came to a screeching halt. This could be what happened.
Food for thought.
OP - More info needed..
Was the case in the chamber fired, The case that was wedged a live round? Empty? Pushed in bullet?
I have seen some crazy AR shit. Primers that blew and flew into the opening of the carrier key as well as spent cases that bounced back into the upper and were completely turned around.
The second incident happened when the spent case bounced off a barrier and went back inside the upper.
I am willing to bet that in addition to his ejector or buffer being out of whack, the chamber is probably tight as well.
Was the case in the chamber fired, The case that was wedged a live round? Empty? Pushed in bullet?
Was the case in the chamber fired? NO
The case that was wedged a live round? EMPTY
I JUST INSTALLED NEW EXTRACTOR + EJECTOR WITH NEW SPRINGS AND BLACK DONUT ON EXTRACTOR, GOING TO THE RANGE THIS WEEKEND TO TEST FIRE, WILL GIVE YOU A REPORT WHEN I GET BACK
THANK YOU VERY MUCH FOR ALL INPUT AND ADVISE, APPRECIATED IT.
I would remove the donut first.
Was the case in the chamber fired? NO
The case that was wedged a live round? EMPTY
I JUST INSTALLED NEW EXTRACTOR + EJECTOR WITH NEW SPRINGS AND BLACK DONUT ON EXTRACTOR, GOING TO THE RANGE THIS WEEKEND TO TEST FIRE, WILL GIVE YOU A REPORT WHEN I GET BACK
THANK YOU VERY MUCH FOR ALL INPUT AND ADVISE, APPRECIATED IT.
Failure2Stop
08-03-10, 05:47
Was the case in the chamber fired? NO
The case that was wedged a live round? EMPTY
I JUST INSTALLED NEW EXTRACTOR + EJECTOR WITH NEW SPRINGS AND BLACK DONUT ON EXTRACTOR, GOING TO THE RANGE THIS WEEKEND TO TEST FIRE, WILL GIVE YOU A REPORT WHEN I GET BACK
THANK YOU VERY MUCH FOR ALL INPUT AND ADVISE, APPRECIATED IT.
The o-ring should only be used when there have been otherwise unsolvable extraction issues. You do not have extraction issues. The o-ring may be causing ejection issues. Lose the o-ring and test fire.
Was the case in the chamber fired? NO
The case that was wedged a live round? EMPTY
I JUST INSTALLED NEW EXTRACTOR + EJECTOR WITH NEW SPRINGS AND BLACK DONUT ON EXTRACTOR, GOING TO THE RANGE THIS WEEKEND TO TEST FIRE, WILL GIVE YOU A REPORT WHEN I GET BACK
THANK YOU VERY MUCH FOR ALL INPUT AND ADVISE, APPRECIATED IT.
Very interesting. Keep us posted.
The o-ring should only be used when there have been otherwise unsolvable extraction issues. You do not have extraction issues. The o-ring may be causing ejection issues. Lose the o-ring and test fire.
True but adding more extraction force, if needed, with an o-ring has some advantages over using a heavy-duty spring. It should last longer as heavy-duty springs have higher stress. But agreed that one should never use both an o-ring and a heavy-duty spring for three reasons:
1. No gun should need that much force.
2. Heavy duty springs may break sooner.
3. May not allow bolt to close over the case rim.
I have two questions.
1. Was the picture taken at the range or did you try to recreate what you thought you saw at the range when you got home? I only ask this question because I'm still having a hard time seeing how the conditions in that picture came to be.
2. Were you able to get to the range this weekend?
Vince
Nugentforoffice
08-18-10, 07:09
I have two questions.
Was the picture taken at the range or did you try to recreate what you thought you saw at the range when you got home? I only ask this question because I'm still having a hard time seeing how the conditions in that picture came to be.
Vince
DITTO...It just dosen't seem possible!
I have two questions.
1. Was the picture taken at the range or did you try to recreate what you thought you saw at the range when you got home? I only ask this question because I'm still having a hard time seeing how the conditions in that picture came to be.
2. Were you able to get to the range this weekend?
Vince
HI VINCE,
THE PICTURES ABOVE I TRIED TO RECREATE WHAT I THOUGHT I SAW AT THE RANGE, MY FRIEND ALSO SAW THE SAME THING, I DISCUSSED WITH HIM AND SENT HIM THE PICTURES BEFORE THIS THREADS GET ONLINE.
AND I'M SO SORRY DID NOT GET TO THE RANGE AND TEST OUT A NEW PARTS, WAS WORKING THE LAST 2 WEEKEND, HOPEFULLY GOING TO THE RANGE THIS WEEKEND OR NEXT WEEK, WILL KEEP YOU ALL POSTED IT
ONCE AGAINS THANK YOU VERY MUCH FOR ALL OF YOUR INPUTS, WILL LET YOU KNOW SOON.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.