I'm really surprised that the improved minnie shoots so good from your pistol. I have that mold, but never shot it much because it didn't shoot too good out of my 1 in 48 twist rifle, and it was tough to load because of it's length.
It makes me wonder if your pistol would like the 250 grain REAL or not.
Hey Tommy, I have an idea for you to try. The hollow base portion of the improved minnie is quite deep, and contributes to making that bullet very long and heavy. Maybe you could experiment trying to shorten it a little bit, then it would be more similar to the REAL bullets in several ways.
Why not first try to cut off the hollow base portion of the improved minnie and shorten it? I think that the hollow base is too thick to expand much if at all anyway. It would probably remove about 50 grains of lead or more, and that way you could start testing accuracy and recoil of a lighter bullet.
If you don't like the performance of this homemade "wadcutter" design, then you could try to trim some of the front of the minnie off and leave the hollow base alone, and test it again that way. I realize that you are changing the balance of the bullet, but maybe it will shoot okay for short range and maybe not. And then you will know if your mold has more than 1 application (use). You can always remelt the lead that you cut off, and the minnie has a lot of thin rings around it which can help you measure where to cut it off at the same place each time to compare results. So maybe this is how you can start to do a few performance experiments.
Maybe you can use a file or some kind of cutter as long as you make the cut edges smooth.
I would recommend lubrication of some kind, and don't forget about trying an overpowder wad or card that I mentioned before too.
You like the heavy recoil? Moderate recoil is okay, but too much can throw off accuracy.
How far away from the target are you shooting from to get such good accuracy?
What about shooting patched round balls, accurate?
I can see shooting the 300 grain minnie for more penetration when hunting, but sometimes shooting at paper targets doesn't require so much power.
Let us know us how everything works out,
Steve