I recently acquired chunk(6inch dia. x 12" ) cylinder shaped metal and is supposedly 4140. It has what looks to be a serial and a date. serial looking number is something like "J-107564" and the date is like 10-03-2016.
I've lurked and read alot in the last year quite abit here. Didn't I read somewhere on here that you can ID the metal with those numbers? I've searched online off and on for a month or so and I can't find much about serials and metal. Any help would be greatly appreciated as I was going to attempt to construct a post anvil or similar with it. If I can find more solid info about it.