From a backyard gunsmith, (will work/experiment on my own) on older Colts. I have 2 older colts, a new pocket & New Police, both in 32 Colt. Took measurements on bullet diameter between 32 Colt & 32 S&W, not significant enough to seam unsafe. 1st purchased a a Police Positive cylinder in 32 S&W long. Couldn't get to work in either. Next bought a complete assembly crane & cylinder. Fit both guns, lock up good. Took to the range, cut a hole in the bottom of a box about 5? wide, inserted barrel so cylinder gap was mid point in box, (note, tape box down). My results, in New Police, safe, minimal scouring of powder, no sign of lead shaving. New Pocket, not safe, although no lead shavings, scouring was heavy, stippling from powder left & right corresponding to position of refiling grooves, my interpretation cylinder gap too large. A possible suggestion, (never tried), maybe a Hallow base wadcutter. Could a 38 S&W cartridge be crimped to .357, 2nd if it could, could it be seated in the cylinder?
Dusty