My take is that you'd have to shoot a 77/22 many, many thousands of rounds for the bolt to need shimming. The older Remington 500 series rifles have a two piece bolt, and some of them do need shimming now, but it's not a big deal to do the shimming. I have a 77/22 Magnum that shoots great, like well under 1/2" at 50 yards for five shots. I personally like the Ruger 77/22 series better than the CZ, but that's just a personal thing as the CZ's will shoot very well after a trigger job. I have a CZ in 17HMR that is also very accurately after I did the trigger fix. The Ruger magazines do need adjusting to get best performance from them, which is easy to do. Just disassemble them and wind the spring as tightly as you can with your fingers when reassembling them, and you'll never have any feeding problems as long as they are kept clean.
I like the hefty feel of the 77/22 series as they are much like my deer rifle in weight and balance.
Don
