yes you can "DoubleTap maintains in their literature that the .450 SMC cartridge can be safely fired in any .45 ACP pistol, revolver or carbine which is rated for .45 ACP +P ammunition, no modifications required." but more frequent recoil spring replacement or a heavier spring would be advisable

Yes you can Buuuuuut, Unless you've got boxes of unused 450 super/smc ammo just laying around, then I'd just stick to that .45 ACP ammunition.

Hi Michael and welcome. Yes Sir you can. Just be aware that most manufacturer's warranty their firearms only with the usage of the stamped caliber of the firearm. Just be wary of a potential way around a warranty claim. Cheers, stay safe and enjoy!