Thanks everyone. Top Jaw, in particular thanks for the advice on proportions. I just looked at pictures and more or less winged it. I thought my divisions were off a bit but having some guidelines like 5ths will help on the next. I could "slenderize" the tip on this one, but I think I may leave it as - is and find a new horn. My son is quite artistic and liked the idea of trying his hand at scrimshaw after looking at some pictures, so I may try to find some more fitting horns as a palette.
In the meantime, this horn meets the immediate need of having something to go with my rifle!
And yes, horn work was surprisingly satisfying and definitely addictive.
Thanks.