Prepare for a long story.
I started reloading long before I got into Bullseye, and ended up with a load that was 4.0 grains of Bullseye with a 200 grain semi-wadcutter and whatever brass I picked up on the range. I think I picked that load because of the way it felt rather than any other factor. As my accuracy got better, I became more interested in optimizing accuracy. I had just bought a Kimber Gold Match, and decided to see just how accurate it was, so I put it in a Ransom Rest and tested my standard load. I was horrified to see that if gave me a 3" group at 25 yards, so I started a program to find a load that would perform better in that gun. First I sorted my brass. I decided to use only Federal and Winchester.....mostly because I had more of those than anything else. Then I trimmed all my brass to the same lenght. Then I loaded up a whole bunch of different loads with different lead bullets, different powders, and I tested them all in my Kimber in a Ransom Rest.
What I found was that I was able to get a 1" group out of the same Kimber that gave me a 3" group before. I was able to get this whether I used Bullseye, Tite Group, or Win 231 (the three powders I tested) I was able to get this with a 185 grain SWC, a 200 Grain SWC, or a 215 Grain SWC. Of course each bullet required a different load. (about a zillion combinations) But guess what load worked best with Bullseye Powder and a 200 grain SWC. You got it, 4 grains of Bullseye! So what was the difference? I used just one brand of brass, either Winchester or Federal, and all the brass was trimmed.
I haven't developed a load for the wad gun yet, and I plan to do that this summer......but on a good day I can put 10 shots in the same hole (one handed) with that same load, 4.0 grains of bullseye in a federal case and a 200 grain SWC that I cast myself. I have enough Federal now that I use it exclusively for Bullseye. (Not because I think its better, but because I want to keep everything the same.) I use the Winchester for IDPA, and for IDPA I don't bother to trim the brass.