Gas Key Issue

[No Bananas]

I haven't cleaned an AR in a long time. After 500 rds through a new one, I decided to give her a full cleaning. Now I remember why I hate cleaning the ARs so much....and I haven't even shot ammo I thought was that dirty! From now on I'll do cleaning at the 1000 round mark.

A portion of the gas key lip had slightly been dented inward. Only slightly, and had a carbon build up on it. All 500 rounds have been trouble free. No hiccups at all. So, I don't think it was an issue. I got out my file and and filed it down, and corrected the inward dent. In retrospect, I should have let it be. The dent is now smoothed out, and the gas key lip is smoothed on that side...about 1/16 of an inch long ( on the inside of the key lip). I would post pics, but my camera can't get definition that small. Should I be concerned at all about the lip being slightly too wide and not providing the proper seal/meet up with the gas tube? Again, it's only slight. I plan on shooting it next weekend to check function.

[Quib]

Well, pics of course would be ideal. And the -23&P has a procedure for straightening out a bent or damaged carrier key.

The gas tube to carrier key seal actually takes place further down into the carrier key, not at the mouth of the key. If you dressed out the damage, and maintained the existing contour of the keys mouth, you should be ok.

One thing I’m wondering about though….how did the mouth of the carrier key get damaged? Was it from handling? Or, is your gas tube alignment off? Is the carrier key striking the gas tube during firing?

A quick check can be made of the gas tube to carrier key fit.

http://img.photobucket.com/albums/v489/Metroliner/gaskeygastubecheck.jpg



ETA: If cleaning the bolt carrier group is tedious, you might take a look at my method of cleaning....... ----> https://www.m4carbine.net/showthread.php?t=35490

[No Bananas]

Well, pics of course would be ideal. And the -23&P has a procedure for straightening out a bent or damaged carrier key.

The gas tube to carrier key seal actually takes place further down into the carrier key, not at the mouth of the key. If you dressed out the damage, and maintained the existing contour of the keys mouth, you should be ok.

One thing I’m wondering about though….how did the mouth of the carrier key get damaged? Was it from handling? Or, is your gas tube alignment off? Is the carrier key striking the gas tube during firing?

A quick check can be made of the gas tube to carrier key fit.

http://img.photobucket.com/albums/v489/Metroliner/gaskeygastubecheck.jpg



ETA: If cleaning the bolt carrier group is tedious, you might take a look at my method of cleaning.......Link----> https://www.m4carbine.net/showthread.php?t=35490

Great info! Thanks! What/Who is 23&P?

[Quib]

Great info! Thanks! What/Who is 23&P?

Glad to help. :)

Follow the link in my response above. In it you will find a link to the -23&P Maintenance Manual, and the -10 Operators Manual. Look right above where my pictures begin.

[No Bananas]

Great Link!:cool:

I don't know if this key was prior damaged before firing or not. I did the test on both my ARs and both passed just fine. I did, however, notice that the rifle in question's gas tube is a little wobbly when I put my finger on the end of the gas tube and push on it. My Factory LMT is a bit tighter and there isn't as much movement. n However, the rifle in question is FF and the LMT is not. Maybe that has something to do with it? ???

Kinda makes me frsutrated, as I had ADCO put this rifle together for me. I thought I wouldn't have to wory about such an issue. That being said, the rifle has shot great, and been flawlessly reliable.

[Quib]

The gas tube should have movement in it, to allow it to align with the carrier key during cycling.

If you have one particular gas tube that appears to be tighter than another, it could be that the tight tube is being pinched by the barrel nut.

[No Bananas]

Thanks for all the great info. Man, I am always learning new stuff about the AR. :D