Quick thought. .32/40 was a Ballard target cartridge and they shot and loaded lead bullets in those days. The .32 Special was a hunting cartridge with jacketed bullets from the beginning. My reference for barrel steel from the era, Keith said he picked up the WWI revolvers and lots of ammo while in the Nat. Guard and 5000 rounds of jacketed bullets and you had a smooth bore. Lead bullets and it would last half of forever. Luck. Happy Trails.