Don't give the other side an inch. Buy the best factory SD ammo, in whatever style you prefer. Most ballistic studies are subject to interpretation, so make your decision on what you will use and buy it. Reload for the range and practice.
Carry the discussion to far, and you get into all kinds of things the other lawyer can play with. Did you get your CHL knowing you were going to shoot someday? Isn't this premeditated? Weren't you looking for trouble by getting it? Why did you have a lawyer on retainer? Did you have an idea you were going to shoot someone someday?
Good lawyers are professionals when it comes to creating doubt. That's their job. It's how they earn their money. I am not lawyer bashing, but I want my lawyer to be better at creating doubt, diverting back to the other side, etc, etc.
While I, like most, have not heard of a case where a SD shooter was hammered for using handloads, I won't set myself up to be a test case. One of these days some legal beagle is going to go down that road, and I don't want to be on it when he does.