AR15 extractor modification?

[Oleg Volk]

John Farnam talks about adding to the original design -- but I have trouble visualizing what he's advising. Could knowledgable folks comment on this?

 

[Badger Arms]

The D ring is an rubber ring that slips over the extractor spring. It is just like a recoil buffer on an auto-pistol in that it prevents metal to metal slamming and damaging of the spring. It basicallystops overcompression and slows the extractor speed. The fallacy here is that you are preventing parts breakage. The reality is that the rubber ring will wear out quickly and itself need replacement. My opinion is that if you replace the spring every so often (Cheap) you don't need the D Ring. If you want the peace of mind, go ahead and install it.

 

[Badger Arms]

Armalite has something to say:

http://www.armalite.com/library/techNotes/tnote39.htm

 

[Oleg Volk]

So where would I find that o-ring?

 

[Badger Arms]

http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=9949

 

[gun-fucious]

i think it was created as a bandaid for 14 inch CARs that had gas port issues

www.Fultonarmory.com sells the D-Fender

 

[Intel6]

They sure want a pretty penny for those little pieces of plastic? Wolff spring company is now offering a replacement ectractor spring that is more powerful to accomplish that same thing.

 

[Badger Arms]

Uh, not QUITE the same thing. What the rubber ring does is impart extra force ther further the extractor moves in an incremental fassion. A strong spring starts out strong whereas the rubber ring will allow a smaller amount of force when a smaller amount is necessary such as when the extractor is snapping over a chambered round. I don't know the dynamics of the extraction cycle enough to know if this is a theoretical or real advantage. I guess only testing can confirm that.

 

[JollyWhiteGiant]

Anyone ever seen a broken extractor spring after 1500 rounds? I am at about 2500 on mine with no problems. I've never heard of one breaking after only 1500 rounds. Maybey after 10,000 rounds when you would expect small parts to need replacing.

 

[Badger Arms]

Broke first extractor spring recently on a rifle that had about 800 rounds of Russian CRAP in it. Other than that, no problems. It's so cheap, you might want to replace it after every 1000 rounds anyhow just as preventative maintenance. Couldn't hurt.

 

[Will Fennell]

I used the WOLFE XP spring

I have a "put together " AR, DPMS complete lower with a BUSHMASTER DISSIPATOR upper. I was having stoppages that were related to poor/inconsistant extraction.

Inspection showed that I had a very weak recoil spring, in the DPMS lower, and what appeared to be a weak extractor spring in the BUSHMASTER bolt.

I replaced both with springs from WOLFE, regualer strenght recoil spring[much heavier than what came in the lower from DPMS], and the Extra Power extractor spring, which was considerably stronger than the spring that came in the bolt from BUSHMASTER.

I don't know whether it was the recoil spring, the extractor spring, or a little of both[I suspect the latter], but the gun is running perfectly now, and has for the last couple of thousand rounds.

Springs are cheap, guns are not.......I change springs frequently



But then, I shoot alot

Here is a pic of the rifle, posted in the Knife&Gun pic thread....