Wouldn’t a slightly shorter shell holder do the same as a small base die? I have never used SB dies so I am asking.
One could file or grind down the top to allow shorter case sizing.
I have found there is a lot of difference in shell holder heights even of the same brand, which effects the case sizing.
Some shellholders can be ground a bit. Too much and you have a stuck case. Someone on another board found 5 thou was all of it.
SB dies don't necessarily bump the shoulder more, maybe even less due to displacement of brass from below. Dies vary, just like chambers tho. One of my SB dies bumps the shoulder exactly same as the standard FL die. But not more.
