that's a .45 ACP - the 45 long colt is an older cartridge design... still a VERY good choice!
Now, you need to find something that shoots that .460 cartridge....
Left to Right:
.460 S&W Magnum, .454 Casull, .44 Magnum, .45ACP, .22LR (NOTE: the 45 long colt is almost exactly the same dimensions as a 44 magnum - case length and overall length).
Even more fun - Left to right:
3 in 12 ga magnum shotgun shell (for comparison), size "AA" battery (for comparison), .454 Casull, .45 Winchester Magnum, .44 Remington Magnum, .357 Magnum, .38 Special, .45 ACP, .38 Super, 9 mm Luger, .32 ACP, .22 LR