I sent a similar message this afternoon to Bushmaster Tech Support but thought I'd let you guys chew on this for a while:
I recently purchased (separately) a V Match Upper Receiver and Bolt/Carrier Assembly from Bushmaster.
After assembly, I noticed that the carrier is binding somewhat inside the the upper. At first it was really tight, but after manually cycling it about 50 times it seemed to have loosened up a bit - but not much. I am concerned that I may have cycling problems and wanted to gather some additional information before I even fire a round with it.
My questions - Is this normal for a new assembly? Will it get better as it is used more?
I bought the original rifle used and I do not know what it was like new.
My existing A2 setup has the bolt/carrier sliding in the upper quite nicely and the difference between the two is significant.
I suspect the problem stems new bolt/carrier as the old one fits and slides must fine in the new V Match upper.
Any thoughts would be appreciated.