I have 3 Lee bullet molds in 45-70. The first one that I got is the 405 grain bullet and have been using it for some time, sized to .459". I use it in two rifles, a Handi with a 22" barrel and a Sharps replica with a 28" barrel. While I haven't slugged wither barrel the .459" sizing must be right because the groups are small.
The second mold is a 405 grain hollow base mold. I've been playing around with this one for a while and haven't seen any advantage to the hollow base yet. It might be better than the solid base bullet but I haven't proved that to myself yet.
The third mold just arrived last week. It is Lee's 500 grain pointed bullet, actual cast weight is about 480+ grains, and it is a whopper! I haven't had a chance to shoot this bullet yet, but hope that it will be somewhat more accurate at longer ranges due to that pointed shape and extra weight. The 500 grain bullet might be just the ticket for shooting steel. At the price, less than $20 each, you can have get both of them.
Slugging your bore is the best way to determine the best size for your bullets, bore size plus .001", but if you are going to guess then .459" is a good place to start.
Roudy