Jon - Looking at that I have a suggestion. Why not put the short starter on the thinner end of the antler and round the edges off of the thicker end so you can rap the ball to get it started. Then, once you find the correct length you need for the longer rod/muzzle protector you can permanently install it in the existing hole.
That way you're not futsing around changing out parts and still have the 'handle' for heavy seating.