AR15 Extractor Donut

[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.

[StagLefty]

Just read this and realized your in MI-never mind going to Bowers as suggested earlier

[b52buff]

Just read this and realized your in MI-never mind going to Bowers as suggested earlier

No problem I just wanted to throw out the question to see what the purpose was for the donut. I have been to CO and it is a beautiful state. I will look up Bowers next time if I ever get that way again.

This is mind boggling that they don't mention the donut!

[Big Wall]

The donut is an extractor upgrade. One of your guns has it and the other doesn't.

[mc223]

If you are not having ejection issues, dont worry bout it.

Unless you want to worry about it. You certainly can use one if you want.




I dont use the the o ring and never have had a need to.

[trlcavscout]

My BCM came with one in a bag, I havent put it on because extracting is one thing I dont have a problem with!

[FireMoth]

The donut increases extractor pressure, and helps prevent spring kinking that will lead to breakage (took out a spring that had been snapped in half just the other day).

Its not necessary, but it does improve function MOST of the time. Combined with an extra power extractor spring, it can prevent full bolt closure because the extractor wont snap over.
However, the most common problem with ARs far and wide is failure to extract, so i put them in as a fail safe in all of my ARs.

[StagLefty]

I will look up Bowers next time if I ever get that way again.

FireMoth is so good he does internet and long distance gunsmithing

[legaleagle]

I have not seen a Stag with the donut. They seem to come with either a blue or black insert in the spring, which kinda does the same thing as the donut (or at least same theory). However, the donut probably generates more "spring" tension, although I have not actually measured the pressure between the two. More critically, the shape and fit of the extractor on the brass, combined with the leverage from the fulcrum pivot is more important - a bad extractor is not fixed with the donut, etc.

If you are not having issues, I would not worry about it. Too much spring pressure can be another problem, as mentioned.

[YammyMonkey]

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.