I am most likely older and fatter than you but next time I get to Indy I may have to give this a whirl. How many mags do you need for something like that? I currently only have one for my .45.
The HP 45 will fall into Production class, you will need atleast 4 mags on your belt and one in the gun, so 5 total.
I am 38yrs old and 325lbs and have treated my body as an amusement park since birth.