I just recently started having problems with my 9mm build after about a year of shooting it and was wondering if someone could help diagnose the problem.

Just recently I swapped out a 10.5 inch green mountain barrel for a 16 inch green mountain barrel and after taking it to the range, its having issues extracting.

It will sporadically run good then it will chamber the next round and the bolt will close but the extractor will not hook around the case for some reason. I can pull the CH all the way to the rear, release it letting it slam home and will not pick up the round unless sometimes doing that 3 to 4 times. Then others times I have to pull out my pocket knife and pry it out.

I have taken the extractor out and cleaned it thoroughly and it brought up the extraction rate up to about maybe 50%. As you can see from the pictures its clean with no buildup on it anymore. Ive also cleaned the channel the extractor sits in.

I can take a case and manually put it on the bolt face and it grabs the case just fine, looks and feels like a lot of engagement.

I even swapped barrels back to the original 10.5 inch and Im still having the issue so not an out of spec chamber on the new barrel.

Is it possible that the buffer spring has just worn to the point where it doesnt have enough umph behind it anymore to close the bolt hard enough to get that extractor around the case? Or is this a case of a worn extractor?

Here are the specs

CMMG bolt

Green Mountain barrel

Hahn top loading mag block

Brownells modified uzi mags with BHO tab on back of follower

Ammo is 115 gr FMJ reloads of mine, taper crimped to a .375"

Standard carbine buffer spring

Spikes heavy 9mm buffer
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