Lots of good points and advice here already. I have a 5-1/2" magnaported 475 Linebaugh (FA Model 83) and a 5-1/2" non-ported 45 Colt (Ruger Bisley). When I load both with heavy bullet hot rounds, the 475 kicks MUCH less than the 45. So I'd think a 45 Colt that's magnaported would be a joy to shoot....especially if you don't push the limit when pulling the handle on the powder drop.
