I think the issue with damaging the gun is backwards to what you are hearing. You won’t be flame cutting anything or wearing out any forcing cones with .45 Colt. The .460 SW Magnum is having some growing pains with certain powders and possibly certain powder and bullet combo’s that can cause flame cutting and forcing cone erosion. But those all tend to be red hot loads from what I have read. And a good hard cast, gas checked, and properly lubed bullet can be pushed pretty hard. Check out Garrett’s loads if you don’t believe me. But you do have to know what you are doing.