Borrow the .270 for a season or two.

In Iowa you will be using a shotgun or muzzleloader. (there is a rifle allowed antlerless hunt in January in some high population countys) I recommend an 870 in 12ga, Express combo. You will be able to go bird hunting too. My boy knocks the heck out of deer with a cheap CVA Apollo in-line .50 muzzle loader.

If you have friends who hunt, talk with them. I just think that you will not get much use out of a rifle in Iowa.