Re: Southern Colorado Shooting Range
Don't count yourself out....
I'd give 'em a call 1st. I do know they're not allowing any of the .30 'magnums', but something like a 35 Whelen may be OK. I've seen .30-06's and .308's there a lot.... In fact, I don't think they're allowing any of the hot 7mm mags (STW/Dakota/RUM), but my 7mm Rem Mag was allowed (and what one RSO told me was the most they were allowing until they can get clearance from Ft. Carson to go higher).
The Range is using some type of maximum range (distance?) potential of the round to determine what's OK, but call 'em to make sure what you're bringing is gonna be within limits.