If your interpretation of ‘tactical’ means engaging in extended firefights with Kodiak island brown bears, Wild West Guns has just the secondary weapon system you need. Their drop-in .460 Rowland conversion kits will turn your .45 ACP 1911, M&P or XD-45 (pictured) into a bruin-blasting beast spitting out 230-grain punishment at 1250 fps. Suck that, 10mm!
Click here for more info on the .460 Rowland cartridge itself, if you dare.