.44-77 bullets for a 19-twist barrel?

[Kurt]

I'm going to carry this PP gas check a step farther.
   
This bullet is nothing new, it started back in the 1800'rds but it's not NRA legal for matches because it's a permanent attached wad. This PP bullet is groove diameter and shoots very accurately and it also scrapes the fouling.
I can attach them using my swage press and dies.
   
But these wads are NRA legal to use because they are not attached to the bullet base, they are considered a wad.
I can cut them with a Corbin die on my swage press from copper flashing sheets. Notice the dome, those wads are bore diameter and the wad is seated below the bullet base with the raised portion to the powder or a card wad between it and the powder and when the charge goes off the copper wad expands and fills the grooves. This seals off any gas and also scrapes the fouling.
These wads were developed for volley firing keeping the bore clean.