I'll say again, it does have enough carbon in the barrels to harden and it does indeed harden from TIG welding and the self quenching caused by room temp barrels. No reading between the lines or specs. BTW, .40% is plenty of carbon to facilitate hardening. 4140 can achieve 500 Bhn or 50 ish RC. That's pretty dang hard. Weld puddle borders can have concentrations of alloying agents, especially carbon, that facilitate even higher hardnesses. I have the dull files to prove it.
I don't believe 20th century LC Smith barrels were 1020 for a minute. 1020 is stuff you use for making muffler tubing not gun barrels. If you've ever machined 1020 you'd understand that it isn't suitable for machining a gun barrel either. It is so long grained and leaves such a poor finish that you would have to invest in additional finishing processes that cost a lot of time and money.
Last edited by Chuck H; 01/26/12 04:50 PM.
