Forging a hammer

[Alarion]

I'm trying to forge a hammer head like this

I'm starting off from a 4 pound hammer like this

Any advice about forging and subsequent heat treatment?

 

[Stacy E. Apelt - Bladesmith]

Forge it hot - 1200-1250C, and make sure the head is fully soaked. Start by making it octagonal. Then draw out the peen. Round the face and peen on the grinder. HT should be targeted at Rc48-50. If you know the alloy of the head you are using you can look up the HT, if not, HT as if it was 4140.I'd start at 290-300C and work up in 15 degree steps after testing the Rc from there.

BTW, you can cut the peen bevels on your band saw easily,too.

 

[Alarion]

Thanks.
I already did exactly that: started the octagonal section, then the peen. Figured that if I forged the peen first, it would be quite hard getting a decent hold on it with box tongs afterwards (I'd have to forge eye tongs, while I have box jaw tongs of sufficient size).
I tried to forge it to shape as much as possible, as I want to retain all the metal (weight) I can.
I forged it bright orange... dunno about the actual temp, I have no way to find it. I'm using a hand cranked coal forge fueled with metallurgical coke.
My tech level is about second half of the XIX century

I don't know the steel, but I plan to triple normalize it, heat it to non-mag and then a little more, let it soak for at least 5 minutes and then quench it.
I read somewhere that I should quench it under a strong flow of cold water hitting the center of the face. If I quench it by dipping, the corners would get much harder than the face... or so it said. Is this correct?
As for temper, I was going for a blue color, holding the stuff at temp for at least a half hour, given the section of the steel.
Again, I have no other way of judging temp.
A file should bite the steel, otherwise it's too brittle (dangerous!)