Due to the fact that minie balls don't expand to fit the rifling when loaded into a case I am going to try this modified bullet in my .577 Snider. The idea is that the bands will make a good gas seal and engage the rifling while the nose rides the bore. I've had the Lee 578/478 M mold since I bought my first Snider but after one try it has been collecting dust.
The work was done in a 4 jaw on the lathe with a small boring bar. I powder coated these two to show up the result of pushing one through the bore. Hope to try them out this week.