Something else I thought of.. possible you are seating your bullets a bit long. They could be hitting the lands before you get the bolt closed.

We still don't know enough about your issue except your brass oal is within spec. We don't know about shoulder measurement or how deep your seating your bullets.

If your buddy's brass chambers fine and your doesn't there is no doubt a difference somewhere and measuring those data points are the only way to find out exactly where the issue is.