Bullet fit

[Kurt]

Jim,

I'm not a slug gun shooter but I have played with the patched round ball ML rifles using PP bullets and no mater how soft I cast those bullets they would just not bump up enough to fill the grooves. The round ball M/L have deeper grooves than what we use in our suppository rifles
But the M/L you're talking about have shallow grooves like what we use and also they have a faster twist. A loose fitting bullet that slides down with the weight of the rod will fill the grooves and make a seal. The advantage the M/L has over a cartridge rifle with a loose fitting projectile is it's held inking with the bore. A cartridge rifle if not loaded properly can endue with runout.
I have front loaded a sharps using the same case that is longer than what I use but I wanted to fit it tight into the throat to help the seal, de priming and cleaning it and recharging the case flush to the case mouth and pushing a bullet down on the case like some of the Schuetzen and bench rest shooters do to see if it improves the over all accuracy and it did but it's time consuming doing it.
It was good for the curiosity

Kurt