Why not get an 1917 Enfield action and send it to Ed Hubel for chambering his .585 Hubel Express? I shoot a 1150 grain (that's a 2.62 ounce cast bullet) traveling at 2200 FPS getting nearly 8 and a half foot tons of muzzle energy, that's about two foot tons more muzzle energy than the famed .50 cal BMG round, and sufficient to stop an angry Studebaker or a unfriendly Blue Whale, making the Winchester round look like a 22 short. A lot less work and cost as He will do the heavy lifting chambering and metal work for about a grand, you do the sights, wood and magazine if you want 3 shots yourself. I use mine to cartwheel pigs running downhill in Pahala, my record is catapulting one 10 feet in the air.