In PA you would be careless to shoot at anything living at 500yds regardless of caliber. Over here in the flatlands you can see for miles. I'm not saying you SHOULD take a shot at a deer at 500yds. I'm saying:
1) People make up for their lack of accuracy with power and
2) People don't actually know or realize the power of the caliber they have.
A 270 will blow a hole clean through regular 1/4" thick steel plate at 500yds. I have seen it. I know my rig. I know how to use it. If it were legal to use my 243 in Ohio why would I not use my 243 at any comfortable range I am capable of instead of trying to get within 100yds with a crappy 12ga? If you dont feel comfortable in your abilities then get as close as you can with your shoulder mounted cannon. I would prefer not. A 223 @ 300yds/243 @ 500yds over a 12ga @ 100yds any day all day long.