Well, ol’ John was a bit ahead of his time, no? I shot a cement truck with a 1911 one day. Just a bit over 300 meters. One shot on a bet, won a case of beer.
I’m thinking if one wants 3K FPS with the cartridge they ought to consider a 4 piece sabot with proper OD and a flechette dart for the “bullet”. They could call it the .45 Creedmoor Killer.