Needed a V shaped hot punch for a project so I scrounged through my limited scrap pile and came up with this very rusty 1/2" drive breaker bar that I picked up at the scrap yard. Cut off about 7" and threw it in the forge. Got the business end to the required shape and decided to heat treat it. Not because it will need it but things are a little slow and I figured why not. Got it past nonmagnetic and quenched it in oil. A file dug into it like it was made of wood. Tried again with the same results. Tried a third time but did a water quench and the file still dug in. I picked up the other half that I cut from and wire wheeled the heavy rust off and there it was just as I suspected "made in China". Another piece of imported crap.

Breaker bars aren't supposed to get hard, they're supposed to be springy tough or they tend to snap off when they work harden. Worth a try though, let us know how it works as a punch. Please.

I grab crow bars and speed bars at yard, etc. sales for stock shelf. Most crow bars are at the high end of medium C and speed bars are bordering high C.

(For those who don't know,) "Speed bars" are those flat nail puller, pry bars, frame carpenters carry. Thin flat stock sharp ends with "V" nail slots for pulling nails and shaped to pry and take hammering. Tough as can be, good steel for the stock pile. IF you have an extra everybody should have one for oh say taking pallets apart without destroying the boards. 

Frosty The Lucky.

The last time I needed a V-shaped punch (more of a chisel, actually), I cut an 8" section of HC angle iron from a bed frame, flattened the top 6" for a handle, and reduced the 90° of the bottom end to about 60°. Heated to non-magnetic and normalized, because I knew I'd be using it for hot work. Makes it easier to sharpen, anyway.