After killing lots of varmints over about 70 years and using .17HMR, .22LR, .22Mag, .223 Rem, 243 Win, 6mm Rem, .270 Win, and .30-06, I have to warn you about those larger, heavier, less frangible rounds/bullets if you're shooting in fields, or where homes or people outdoors might be injured by either a miss or a ricochet off the ground. A 30-30, .270 Win, or 30-06 with factory hunting loads might ricochet and be dangerous to a nearly two miles beyond the point that it first hits the ground or other hard surface. Other rounds mentioned, may also ricochet and go a shorter distance than the "heavies", but can go a mile or so and still penetrate into a home. No shot at a critter is worth hitting a person, home, vehicle, or any domestic animal, or even hitting but only wounding any living mammal/etc.
Have I had ricochets, certainly, but in a relatively safe direction and distance. Today in my part of Maine, we've had tremendous development of homes in the rural zones and most of the places that we used to enjoy hunting varmints and are unsafe to shoot in. Homes are also often built in wooded areas that used to be safe backstop areas.
One of the last times I hunted woodchucks with my .30-06, I saw one at the top of a knoll in a hayfield, but declined to shoot, even though I knew there were no homes behind and there was a huge lake beyond that. So, my buddy and I went to the left at least a hundred yards and across a hedgerow with a stone wall, circling around the critter then to where we could see along the top of ridge where the chuck was located. When we got to the right point behind the wall and looked for the critter, it was NOT a woodchuck, but a lovely young woman lying in the grass, catching the sun while her boyfriend was off hunting woodchucks!!! My knees grew weak, just thinking about what could have happened if we weren't such careful hunters. We told the woman that it's not safe to lie down in a field, especially with hair the same color as a woodchuck, and that it would be safer to wear some orange, especially a hat.
JP