Don McDowell wrote: ↑Thu Sep 14, 2023 9:29 am Thanks KW.
One thing I can say for sure from having spent more years messing with the dual diameter bullets than anybody, that's a whole nuther can of worms from straight sided patched or grease groove.
There's a point where you cross the balance line between base length and nose length that will cause all manner of grief, or joy.. Base diameter plays another huge part, and it runs headlong into the same thing as getting into the diameter of a straight sided bullet, in that there's no place for the displaced alloy from the lands to go except over the base causing finning. Base major diameter being to long will give you some weird stuff, and to short will give you and unbalanced bullet there is probably no hope for especially when you get past 300 yards.
I'm getting pretty well convinced that the wad stack under the dual diameter isn't quite as critical as with a straight sided bullet. Mostly leaning towards less is better. I'm still working on that when I get the chance, but so far consistent groups are indicating that to be the case
Paper thickness I'm still on the fence about, and believe that will come down to chamber leads and diameters.
Don,
The more I think about it, the 2 most accurate DDPP bullets I have shot to date have VERY little major dia on them.....hmmmmmmmmmmm