I notice when chambering a round in my Brno ZKK-602 that the bolt closes with some effort. Upon extracting a case (fired, unfired, new and unloaded, it doesn't matter) there is a wiped area around the circumference of the rim ending in a slight burr. Examination of the boltface indicates no rough or sharp edges. With the price of .416 Rigby brass, I would like to eliminate this glitch. Can anyone point me to the problem and solution?

BTT

Usually this is caused by the chamber and the allowable and/or usable bolt diameter being non-concentric. The center of your chamber is offset to the center of rotation that your bolt turns in and when you close the bolt it is trying to actually shear off a piece of brass case in order to close.

On a CHEAP rifle you can enlarge the bolt-face a little and sometimes that will cure it. On a BRNO....

It is usually caused by a offcenter chamber OR the receiver threads being cut offset to the boltways.

Either way, ouch!

Michael S.

Thanks for the info Michael. I was afraid that was what might be going on with the gun. Sounds like a trip to the gunsmith to me.