If you mean rifles, its quite a jump from a .22 to a 30 or 40 caliber. If you mean pistols, the 38 special and 9MM are pretty mild and fairly cheap to shoot. If you want to hunt varmit and maybe deer, the 243 or 25-06 would fit the bill for most. Give us a little more info on what you want to do with the gun.

BTW, Welcome to the site.