IMO That the Marlin Model 60 with tube mag 14 round is an amazingly accurate .22LR rifle, it is semi auto and is MORE accurate then a ruger 10/22 out of the box. Not to mention, half the price. Not to mention you have to spend $$$$ more money "$400+" to mod a ruger 10/22 to even come close to the accuracy of a Marlin Model 60.
It is, hands down, the best .22LR semi-auto for the money.
GET ONE!
EDIT TO ADD: I am sorry, I didn't see that you were looking for a bolt. Well, if you do decide on a semi auto, give that a try. Its a world famous rifle and has sold more then any other .22 semi auto rifle in the world!