Most comments are correct. You are not likely to run into any high velocity .32-20 factory loads today. Someone said they were phased out in the 1960s, but other sources give 1950s, possibly both dates are true depending upon manufacturer. For sure, if factory ammunition has lead bullets, it is suitable for use in any revolver chambered in .32-20. Best approach is to reload, far, far less expensive if you plan to shoot much. I will shoot several hundred rounds of .32-20 every month, all reloaded. I use 100 grain .313 cast lead bullets from Missouri Bullet Company over 3.5 grains of Bullseye propellant, very accurate, never had a problem with that load.