Yep, it's the squirrels.
Some states have determined that using rifles is not fair chase, so they disallow them. Some might argue that it is because of the closely populated areas, but at least oneof the no rifle states I can think of have acres upon hundreds of acres of open country corn fields, so that line of reasoningmust be disqualified.

I say stay within the laws of your state and if your state let's you use a center fire rifle, and if you find it ethical.....by all means use it.

C. Davis