After looking at the hunterman bullet link in someones post, i went and pushed a great plains bullet down the bore in my .45 and took measurements of .450 and .461.

What do you think would work best? .451? I would like it to load without a short starter but not to loose. Doesnt look like hunterman sells anything with a hollow base so i may have to email BS and see what he has.

The Whitworth bullet from hunterman looked interesting.