View Full Version : Help!!!!!!
Please help with this.
The best I can classify the malfunction is this…
I think it’s a failure to eject. Here is what it looks like.
The bolt is jammed ¾ of the way open and there are 2 cartridges forming a V inside the receiver.
One cartridge is empty and has been extracted. The other one has been stripped from the mag, but can not enter the breach because the spent shell is also in the receiver.
It looks a little like the V from a double-feed, but instead of both shells being full, as in a true double feed, one is empty and has not been ejected.
It seems like when the rifle is squeaky clean this problem goes away for a bit…But after only a few mags are fired…It starts malfunctioning all the time.
I added a rubber O-ring on top of the ejector spring and it made it a little better, but it did not go away.
I also bought one of those heavy duty extractor springs but have not replaced it yet.
Any suggestions???
Jay Cunningham
08-20-10, 12:02
Before jumping into any further diagnosis...
Do you generously lube your AR?
Have you tried different magazine/ammunition combinations?
What make/model is your rifle?
Stock Bushy M4. Generously lubed. Aluminum and P-mags tried.
Jay Cunningham
08-20-10, 12:16
Ammo?
Did it just start doing this?
Jay Cunningham
08-20-10, 12:18
The o-ring is not going to necessarily do anything here - that is for extraction (which seems ok) not ejection.
Your ejector and spring are housed inside your bolt. You may need to replace the ejector spring, but I'm trying to eliminate anything glaringly obvious first.
William B.
08-20-10, 12:19
How many rounds have you fired through it?
Mostly Wolf but some brass too with same results.
Just started doing this after about 500 rounds?
Jay Cunningham
08-20-10, 12:29
There is an outside chance that your carbine is short-stroking in a particular way. Is there any evidence at your front sight base of gas leakage? Is your FSB straight or is it canted at all?
Also check your gas key on top of your bolt carrier and make sure the screws are tight. I would be shocked if they are properly staked, but they could be I suppose...
Understood.
What do you think the chances are of a "bad" extractor?
Jay Cunningham
08-20-10, 12:47
Understood.
What do you think the chances are of a "bad" extractor?
Unless I am misunderstanding you, it sounds like it is extracting.
If it were short stroking I doubt it would pick up the second round right?
It's only partially extracting.
Failure2Stop
08-20-10, 12:51
I bet that if you thoroughly clean and lube your ejector and lose the "o"ring your problem will go away.
That is, unless there is a low-percentage problem with your rifle, which is difficult to determine unless the easy, cheap solutions are tried first.
Failure2Stop
08-20-10, 12:55
It's only partially extracting.
There is no such thing as partial extraction.
Failed extraction happens when the case is in the chamber, at the point of greatest force. The extractor does not fail once the vase has been pulled from the chamber, there are no events or forces on the fired case that would cause the extractor to lose grip on the rim.
As Jay said, you have ejection problems- linked to the ejector, excessive extractor tension, and possibly bolt speed.
There is no such thing as partial extraction.
Failed extraction happens when the case is in the chamber, at the point of greatest force. The extractor does not fail once the vase has been pulled from the chamber, there are no events or forces on the fired case that would cause the extractor to lose grip on the rim.
As Jay said, you have ejection problems- linked to the ejector, excessive extractor tension, and possibly bolt speed.
OK, Thanks for the help. I'll switch bolts and see if that cures the problem and work from there.
Many thanks Guys!!!
If it were short stroking I doubt it would pick up the second round right?
I guess it depends on how 'short' it's 'short-stroking' or if that's even possible.
I had a rifle with a leaky gas block and it would cause intermittent short stroking. I would get full extraction and ejection, but it would not pick up another round. Maybe if it cycled back just a little further it would have picked up a round, but at that point I imagine I wouldn't have noticed a problem.
I'd be curious to see what happens if you start running another bolt as the OP stated. If that seems to resolve it then i'm with Jay, it seems like an ejector issue.
lanceriley
08-20-10, 19:14
one round is live and one round is spent forming a v.
my observation:
I woudn't think it's short stroking. considering that the bolt was able to strip a live round from the magazine.
What was the hammer position? was it hammer up? if a live round was stripped from the magazine and the hammer was up... this is definitely not short stroking.
I think it's more of an ejection problem. check ejector. it might have a weak spring.
one round is live and one round is spent forming a v.
my observation:
I woudn't think it's short stroking. considering that the bolt was able to strip a live round from the magazine.
What was the hammer position? was it hammer up? if a live round was stripped from the magazine and the hammer was up... this is definitely not short stroking.
I think it's more of an ejection problem. check ejector. it might have a weak spring.
Correct. The general consensus seems to be the ejector as the problem.
Thanks for your input.
Jay Cunningham
08-20-10, 20:05
Guys, I used the following terminology:
There is an outside chance that your carbine is short-stroking in a particular way.
Note I said that this was a possibility but not the probable cause - no need to get hung up on it.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.