Home Forums Hunting & Shooting AR and Tactical Rifles 450 Bushmaster or 458 SOCOM?

Which would you get and why? 450 Bushmaster uses 45 Long Colt pistol bullets, while the 458 SOCOM can use 45-70 bullets. I reload. Both use the same bolt. I've read the 458 SOCOM can use standard AR-15 mags single stacked. Can they 450 do the same? or does it require a different magazine? Just thinking about getting another upper.