Brass not being Ejected

[drift_g35]

I have recently been having some issues with my AR. A while back after almost every round, the brass would not eject causing a malfunction. I contacted Barrett and they sent me a new extractor, pin, and spring. That seemed to almost fix it. I took it out this weekend and put about 200 round through it. I had ~ 4 or 5 malfunctions. When I look closely it looks like the extractor is holding too tightly to the round and when the bolt cycles it only makes it a little ways out of the chamber before the bolt comes back. When I talked to Barrett they said that the bolt assembly was designed for the 6.8 version and used in the 556 version. Meaning the extractor is a lot tighter than a normal ar extractor. I dont want to have to send it to Barrett. I know they will probably fix it but I would like to see if its an easy fix that I can perform. Any ideas?