The convertable 22LR/22mag revolvers will have 2 cylinders, and a bore with the diameter for a 22 mag. 22LR is slightly smaller, so you can shoot them through the barrel, but accuracy might suffer a little (but not always). If you want a rifle that will shoot both, try a NEF Handi-rifle in .22 Mag. You should still be able to use 22LR ammo.