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 Can headspace be too tight?
CA_TX-Cop  [Life Member]
11/4/2007 9:33:14 PM
Trying to finish up a Galil build.

Bolt locks in place, no problems, rounds fit in chamber, no problems, try to eject round from chamber and REALLY have to yank on the charging handle to get it out.

Do I need to get a reamer and have the chamber opened up or do I just "shoot it out"

Thanks... if there is more to it than those two options, please enlighten me.
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WildGoose  [Member]
11/4/2007 10:54:46 PM
It is possible for headspace to be too tight. A lot more of a danger in bolt guns due to the camming action of the trun bolt. This can force the neck of a cartridge past the chamber and into the throat causing greatly encreased chamber pressures. On AKs its not as likely to do this as the bolt will not close on a round when the HS is that tight. Have you checked the HS with guages? How are you closing the the action, by hand or by letting the bolt fly forward under spring pressure? If you are doing this with live rounds(really not a good idea) be damn careful where the muzzle is pointed when you do it. I have seen some kits where the bolt will not close on the go guage but will close on a round. If the bolt will close on a round and extract with out undue effort then it should be good to go. But, if you are having that much resistance extracting the round then you will be better off trying to determine why. There should not be that much resistance if all is as it should be. Is the chamber clear of any burrs or other fouling? What ever you do dont just shoot it out. A little caution is called for in figuring out why the action is that sticky. When you eject the case are there any indications of deformation on or near the case mouth area? Its kind of hard to tell what is going on just reading about it. All in all its does sound like something is not quite right so be patient and careful about looking into it.
Eyegun  [Team Member]
11/4/2007 11:13:15 PM
How big is your gas hole?

Might be nothing, but I had a similar issue with a yugo .223 build I did last week.

I forgot there was a variable gas setting on this particular AK. It was on '3' and would not eject the spent round (Wolf ammo of course). I had to beat the stock on the ground to get the spent case out. I then put the setting on '1' and it functioned perfectly. Apparently a lot of the recoil is taken by wrenching the spent casing out of the chamber.

Again, might be the wrong idea, but it's worth thinking about.

Another thought: A lot of people put too much weight on how a rifle functions by hand, but it's apples and oranges when it comes to comparing manual function with live fire function....that is to say a rifle that functions 'roughly' by hand may function just fine with live ammo.
CA_TX-Cop  [Life Member]
11/5/2007 10:06:11 AM
Gas hole is not an issue, because I haven't fired it yet...

The round will go in when I place it into the chamber, and the bolt will close with no problems WITHOUT a round in the chamber.

If I place a round in the chamber, and let the bolt carrier go, it locks into place exactly where it should. However, that's when I have to OOMPH the carrier back to get the round back out. I have tried this with several rounds and examined the rounds afterwards, there are NO markings on the casings showing that they are being forced past the chamber mouth/end or anything else.
WildGoose  [Member]
11/5/2007 11:09:19 AM

Originally Posted By CA_TX-Cop:
Gas hole is not an issue, because I haven't fired it yet...

The round will go in when I place it into the chamber, and the bolt will close with no problems WITHOUT a round in the chamber.

If I place a round in the chamber, and let the bolt carrier go, it locks into place exactly where it should. However, that's when I have to OOMPH the carrier back to get the round back out. I have tried this with several rounds and examined the rounds afterwards, there are NO markings on the casings showing that they are being forced past the chamber mouth/end or anything else.


Hummm, thats a tough one. I can see why you are tempted to just go ahead and test fire it. For what its worth it sure seems that its just a case of a really on the edge of being a too tight head space issue. Like I said before overly tight head spacing is a real danger in bolt guns due to type of action. In the AK type actions the bolt has little camming power to force the round too far into the chamber and cause a major overpressure event. If its really to tight on the head spacing it would not fully lock up without some extra force applied to the bolt. If you are absolutly sure that its fully locking up with just the rebound spring action then it could be good to go. If I were in your place right now I am not sure what I would do. Its either take it to a gun smith you trust for evaluation or tie it to a tree and use a really long string.
uscombatdiver  [Member]
11/5/2007 7:41:03 PM


Hummm, thats a tough one. I can see why you are tempted to just go ahead and test fire it.


Any other gun and that suggestion would have me wondering, but that is so true with so many AKs. I had a similar problem when I pressed the barrel just a hair back in too far but it was not as easy as you are saying, I had to give it a "forward assist" to get it to chamber the round first. I pressed it a hair back and after a loud "ting" it is functioning very good. Even if that is the problem, there is a good chance that firing it would fix it, but be sure to be as far away as possible when those first shots go off.
tapeo1  [Member]
11/7/2007 9:56:03 PM
It's fairly common for it not to close on a go-gauge. So long as it'll close on an actual round you're fine. Almost all of my builds won't close on a go-gauge but will close on a live round. All these builds have been fired several times without any problems whatsoever.

ETA: I just noticed that you said that you have to use some effort to extract a live round from the chamber.... in that case, I don't know what to say as I've never experienced that. One thing you could try to do is try to press the barrel out a little with the pin in place. Doing this (without pressing too much) may cause the barrel to push out a thousandth of an inch which may solve the problem.
Trotsky  [Member]
11/8/2007 6:25:16 PM
Check for roughness in the barrel chamber. If you are passing a GO gauge, I doubt that you have insufficient headspace.

Here, a GOOD scrubbing with an AR15 chamber brush & CLP would be a first action... insure that there is no serious crap in the chamber. Follow this with a visual inspection using an illuminated boar light down the THROAT.

Let us know if you see issues - remember to rotate the rifle & look at the entire chamber area. It IS possible to polish these - but a headspace check should be performed if you do.
CA_TX-Cop  [Life Member]
11/12/2007 4:22:11 PM
Just an update,

shot it, shoots great, no problems with FTE or anything.

The bolt is having bolt-over bullet failure when stripping off the magazines though. About 1 or 2 in every 10 rounds. The magazines are as high up as they can go, so I'm not sure what the problem is, I'll be posting elsewhere to try and figure it out.

THanks for the input guys. Just to re-iterate, Headspace IS Good To Go!!!
uscombatdiver  [Member]
11/12/2007 5:29:11 PM
Are you using hollow points? They do cause problems (more in some rifles than others).
CA_TX-Cop  [Life Member]
11/13/2007 4:42:41 PM
How would hollow-points affect the bolt picking the bullet up from the magazine?

But yes, I was shooting hollow-points and soft-points. I should be able to get FMJ's into it the next time I take it shooting, but I'm looking at the mags and the mag lock-up as probably being the main problem.
Rob72  [Member]
11/15/2007 11:25:37 AM

Originally Posted By CA_TX-Cop:

The bolt is having bolt-over bullet failure when stripping off the magazines though. About 1 or 2 in every 10 rounds.

I had a similar problem with a WASR- it was bolt/hammer friction, as best I can tell. At least it was resolved by polishing the upper portion of the hammer face, and a bit on the leading edge of the bolt where it rides over the hammer. The bolt was being slowed enough that it couldn't complete stripping a new round. It was also irregular, maybe depended on just how a particular round came up against the feedlips. Just a thought...
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