I wouldn't recommend bills for sighting in a .270, should do that at ~100yds since it's such a hot round and I think bills max is 25-30... they 'might' have a 50 but I don't recall it.
As a side note. I have a membership to a shooting range that is outdoor, has 100yd and 25yd target banks, and is about 5 minutes from Grand Casino Hinckley, i'd have to see if everyone is supposed to have a membership or just one person but I 'might' be able to get us the ability to use that. Bills is nice though for the ability to purchase targets, ammo, rent guns, etc.
Oh and I'm sure most know this but, if you're renting their gun, you have to buy the ammo from them. If you are shooting your own you can bring your own ammo which is advisable since they are not the cheapest place to buy ammo. Also you may want to check I know some ranges require brass only ammo (no aluminum / steel ) I can't remember if bills is like that or not.