Custom Colt Python A member of Colt’s famous and highly collectable “Snake” series of revolvers, the Python was chambered in .357 Magnum. I say custom again because the grips are not factory stock. Note the speed loaders; a quick and efficient way to reload a revolver, mostly used in competition shooting. On a side note, you can tell the barrel length by the number of ribs/vents placed along the top. 2 ribs = 4 inches, 3 ribs = 6 inches and 4 ribs = 8 inches. Why mention that?