I have owned two so far. A 77/22M and a 94/22M. I only use Winchester Super X JHP 40 grain ammo as it has proved to be very effective for dispatching problem critters.
Number one Son has "borrowed" the Ruger and the 94/22M remains with me. I would recommend both rifles and ammo.
If I were in the market for a working accurate .22 Magnum rifle I would give serious consideration to the Ruger RAR.