Daryl

Granted shaving the die will do as you say but it still won't size down the last part of the base of the cartridge that is inside the shell holder . When the chambers were cut on Dutch44's rifle it appears from his description that they are a little undersized at the shell base end. Being a rimmed round the whole base of the shell must go into the chamber. You may get there by shaving the die but you have then forever shortened the die. Sacrificing a shell holder is cheaper and will achieve the same thing or better if it is the base in the shell holder that does indeed need sizing.

As you know dies all have a bevelled shoulder to prevent scrapping the brass and you do lose a little sizing effect from this. By shaving the die you can eliminate all or some this bevel and gain a bit more sizing at the head end of the case.

At the end of the day the method that Dutch is using will probably be enough as the cases may only just need the base sizing down the first time. I don't know if he has tried reloading shells fired in his Henry yet just by resizing in his unaltered die or shellholder.