S&W 455 MKII 2nd Model

[Kraigwy]

Picked up this revolver at an auction The revolver was converted to 45 Colt.
It’s has a mar under the Crain on the right side D^D followed by the number 126
Looking for any info on this revolver.
In size it appears between the N and K frames.
If shooting the 45 Colt what would be the max safe pressure. I only intend to use it on paper or steel targets. Would it be safe keeping the velocity below 750 FPS

Thanks

 

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You can have a gunsmith check that converted revolver first and when you shoot, use low-pressure rounds below 750 fps with heavy lead bullets. Also check each batch and don't use hot factory .45 Colt rounds