My nephew was having that problem on a Rem 700.
Opened up the bolt and found 2 fir needles as well as hardened grease.
Cleaned it all out and reassemble DRY. Works fine now.
While we were at it, we checked out the safety, FOUND the same problem!!
Solvent wouldn't remove the hardened grease!! Took a razor blade to remove it!!
Cost him a nice black bear!!
Now he cleans it up after every season!!
Lesson learned.