Hello,
It would be a grave misstep to try regrinding the axe you have to the shape of the one referenced there even though in a general way the forms are roughly similar. Also regarding #2496 you have some clue to maybe where it comes from although not necessarily. One thing I'm sure of is that no axe was intended to be hammered on after tempering occurred and if the back of your axe is truly concave, that is, laying with the non-beveled side down on a flat surface the heel and toe elevate the rest of the blade along the bit, that would indeed be a curious matter and possibly indicate that you have either damaged merchandise or something other than an axe for hewing beams, maybe hewing spars or masts. Or is it hollowed, being something else altogether? But getting the back side conditioned is the key. The function of the axe would then determine the shape of the bit which would likely be, if not straight, either a slight arch or slightly receding heel and toe.
Greetings,
Don Wagstaff
