AR15 Extractor Donut

[b52buff]

I have a big bag of those O rings. PM me your address & I'll mail you a few.

Don't just buy one from Home Depot. The rubber won't hold up to the heat, cleaning chemicals & (less of a concern) lube combo.

Thank you YammyMonkey but I already have some on the way. I have not taken my Stag Arms to the range yet. I will try it without the donut but my LMT has one so I will have spares for that one.

[espos1111]

The o-rings (#60 BTW) from HomeDepot hold up quite well for a few thousand rounds. Even if you change them every 200 rounds or so, a bag of 10 is only $2.50. After that you shouldn't need one anymore, as the rifle should be well broken in by then. YMMV

[FireMoth]

I do strongly recommend using o-rings designed for fire arms. Depending on heat cycles, solvents, and exhaust gas interaction the rubber o-rings found at hardware stores can suddenly and catastrophically degrade.

Coming apart can bind the extractor causing failure to go into battery, failure to extract, potential damage to the locking seats, and even extractor breakage.

on top of lasting more than a 'couple thousand rounds' the important difference is how the fire arms intended ones break down when they do degrade, which is to go flat and get deformed a bit, but not break apart, or gum up like a normal rubber o-ring can.

Otherwise the o-ring designed to fix extractor problems suddenly becomes the reason for a catastrophic extractor failure.

You don't have to buy $10.00 o-rings, the ar type are cheap too. and its not worth balking over the pennies differences when it comes to keeping your gun running.

[espos1111]

^ I can agree with your statements except... I was not suggesting you use it for a "couple thousand rounds". I DO NOT recommend to anybody they do ANYTHING to their weapon that they are uncomfortable doing. I was in the USMC and am VERY comfortable around these weapons. When I break down the BCG I go through every piece. I also change the o-ring when I clean it, until it is broken-in. I have only had to use it on one pistol, as those are known for extraction/gas issues out of the box, never on my rifles. Also the o-ring/d-ring/doughnut could/should be removed after the chamber is broken-in. It is there for extra extractor power when the chamber is new and tight. On top of all that, It is easier it find a o-ring at HD to use to diagnose a potential problem instead of waiting for your parts in the mail, or finding a shop closer than a HD that is open and has one in stock.

Again, I am not arguing with you, I agree that you should use the proper piece of equipment for the job. I would suggest the o-ring to see if that is the problem, if it fixes it THEN order the correct part. If it doesn't look elsewhere.

[Byte Stryke]

I would suggest the o-ring to see if that is the problem, if it fixes it THEN order the correct part. If it doesn't look elsewhere.

I don't believe there was a problem per-se but instead a difference between two models was noticed.

[espos1111]

I don't believe there was a problem per-se but instead a difference between two models was noticed.

I figured there was no problem with his rifle, but a lot of other people read these for troubleshooting and help. I was just clarifying my first post about the o-rings for their knowledge.

[b52buff]

I just got a Stag Arms model 3 and there was no donut on the extractor. I looked at the manual for the model 3 and there is no mention of the donut nor is it pictured. I then looked at my manual for my LMT and there is no mention nor is it pictured. My LMT has a donut. Stag Arms is closed until Monday.

Can anyone shine any light on the purpose of the donut.

I took my Stag Arms model 3 to to the range today and it operated just fine without a donut.