No problems @ DIA, just follow the TSA rules, check their website. Declare it at the counter, make sure it is in a locked hard case, UNLOADED. You sign a form that is placed inside the luggage and it gets screened around the check-in counter and off you go. The only delay I've had is with ammo. I had 2 boxes of 9mm, well under 11 lbs. but the sceeners were concerned and had to look. Oh well