Bountyhunter wrote: I don't know what the M6 makers say about it, but you can shoot Colt long .45's in a 410 bore. They may not shoot well in a smooth bore, but it is a nice occasional option.

Have YOU actually done this? In an actual .410 barrel as opposed to a .45/.410 barrel? Even if a .45 Colt cartridge would fit in a .410 chamber I would be leery of sending a .452 slug down a .410 bore (not to mention the choke).
gino