I can design a boolit with any check shank we want, so can any of you. The issue gets to be the edge of the check getting wavy if you make one too tall using a checkmaker. At that height and above you'd need a swaging type die to keep the side walls of the checks uniform. Jim Sage sent me a couple hundred of his aluminum chacks this week to play with, what exactly is the issue with aluminum and chrome bores? I've never played with aluminum checks and hadn't heard of this issue before. I'll try and get to this soon, but my immediate priorities are work, (deadline looming), and my CO elk hunt starting the 15th.
Just for fun go to the Mountain Molds website and play around with his design software. Dan has cut a number of molds for me, and he cut the original BDacp molds back in the dark ages. He is a class act all the way.
BD