|Reading the other review, I was concerned when I ordered this. However, it was a good deal on a fully assembled bolt and carrier group that I needed, so I bought it with fingers crossed, hoping it would work and fit. I just got the bolt carrier group today and threw it in my AR and it seems to fit fine. Maybe a little more snug than any of my other AR bolts, but it fits and it cycles. However, I did find that it didn't have enough oil and some parts were slightly stiff, due to this. The bolt itself seemed a little stiff when locking and unlocking (rotating), so I took it apart and oiled it. Now it seems to work just fine and will likely get a little more loose when I get about 100+ rounds through it. Since that is what happened with my take down pins, they were really stiff for about 100 rounds and then began to get a little more loose and easier to manage.
Overall it works, fits, and cycles fine.|