Greetings,
While I have no experience with the 22Magnum, I do own the top of the line 77/22 in 22lr and, with the right ammo, does shoot 1/2" at 50 yards. At 50 yards I can shoot 10 for 10 shooting at expended shotgun shells. At 100 yards, I'm good for about 7 out of 10. Some folks knock this rifle for a .22lr rifle in terms of accuracy when compared to other brands, especially the CZ 452. I also own a CZ American 452, and while the CZ may be more mechanically accurate, I find the Ruger much easier to shoot accurately. It comes down to the factory stock on the Ruger and the fact that it feels like a full size rifle. The Ruger 77/22 is my favorite out of 4 .22lr rifles that I own.