ORIGINAL: BS
Have you tried a hard heavy seat of the bullet, and then, try a softer, or less seating pressure.
I have a 50 with a 1-30 twist that shoots Maxi's quite good with a charge of 115FF.........the groups really tightened when I started using a wad and opened the front diameter up to thegrove diameter. [on the maxi mold]
You also need to maintain a constant fowling in the bore.....very important! Many different ways, justneed to find one that works for you.
I've been seating hard thinking that it leads to more consistent results. What are you doing?
I've got a maxi-mold, a Lee I think from Cabelas, but I don't know what diameter the top band is. I still have some maxi's I poured many years ago with my Dad's smelter, but they are not pure lead. Did you say that your mold's top band diameter was adjustable? or that you modified it be the diameter of your rifle's groove's diameter?
Happy Hunting, Phil