You can shoot any caliber rifle up to .50 cal.
Yes, rifles are allowed.
Yes, semi and full auto are okay to shoot. The habe rentals available as well. They seem to have one caveat though: they asked me not to shoot 62gr green tips (M855) out of my rifle since it's harder on the backstops. They may have a caliber restriction in place as well so double check before bringing the elephant gun.
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