Operate your bolt without a shell in it 20 or 30 times. Take bolt out and look for wear scratches on the bolt . If they are present, see if it is your bolt or if there is a burr inside the chamber that is causing them. I little fine emory cloth will remove them. Should free up bolt for easy operation.
My Ruger 77 had a stiff bolt when I got it a couple years back, and it was a small burr on the inside of my bolt chamber. Wasn't much, but just enough to make operation rough.