45M, Never seen a 25-20 Python but many years ago knew of a gunsmith who did a 41 mag conversion. The photo may be one of his guns. I still have his paperwork around somewhere if I can find it as I was going to have the 41 work done on mine....Below the 41 pic are experimental factory Colt Single Actions in 256 Win Mag., 44 Mag,41 mag and 44 Spec. Thought it would be interesting for you guys to know Colt was almost there... The closest I`ll ever get to these guns is an auction catalog but I love seeing and learning about these handguns....