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....