No reason at all to feel underaxed using stone. Ill be showing examples as well once I finish the handle for it. A great tool to know as a backup. I may have said it before but there was a story of a man who got lost in the woods without his axe. So for some crazy reason he decided to hike something like 30 miles to where he knew there was an old gun barrel. Somehow by the grace of God he fashioned this into a usable axe.
Now why he wouldve expended so much energy, then, even more forging it, instead of simply grinding a stone and either wrapping some kind of handle around or just making a normal mortised handle is beyond me. I personally think he didnt know this skill at all and thats why he was forced to make such a journey. The celt type handle can also make perfectly usable hammers and other tools.