I have a suggestion. Crack a bullwhip that has no lead in the heel for the next 5 or 6 times you crack a whip. You'll get used to it, trust me! A whip I made recently had no lead in the heel, and I ended up keeping it for myself. When I started cracking it, the first and second time my wrist was, as you mentioned, on fire. Now several weeks later, I'm very used to it, my wrist doesn't tire, and I love the way it handles ( I was so close to undoing the heel and putting some lead ). Now when I crack a whip with a lot of lead in the heel, I don't like it much, even when I crack it a lot. There's nothing wrong with a balanced whip. I've just been slowly learning toward the nose heavy preference. I don't like them jacka nose heavy, I still use steel for my handle foundations, I just don't put as much lead as I do in other's whip in my own.
It does take a while to get used to, but trust me when you do, it's awesome! It's much louder cracks with less effort, plus your wrist doesn't hurt when you get used to it.
![TOH :TOH:](./images/smilies/Indy-Hat-Tip.gif)