Case Forming Question

[JRD]

Hello the forum.
New 300 Fireball shooter here. I'm trying to form some brass from Federal 5.56 cases for my Model 1 Sales barrel. I have a set of Redding 300/221 FL dies.

Necking down the brass, timming, chamfering, all went fine for my setup pieces. Using a tip from the forum I seated a boat tail bullet to bring the neck up to size. My neck diameter of a dummy round is good, wall thickness seems good. (This is comparing it against some Whisper handloads for a T/C that a friend gave me to get started.)

My problem is that when I attempted to chamber a dummy round I couldn't close the bolt. Closer inspection revealed that my FL size die isn't pushing back the shoulder enough, so my headspace dimension is way long. The shoulder is approx .04" forward of the already formed cases I have.

I'm using a standard shell holder with .125" depth. I've got the press set for the shell holder to contact the bottom of the die. Marking a fired Whisper case with a Sharpie shows the FL die is sizing the neck and body but not touching the shoulder.

Is there something I'm missing in how I've set up my FL die? I suppose I could modify a shell holder to shorten the .125" height and allow the case further into the die to set the shoulder back farther, but I want to look for something gross and obvious about my set up and maybe contact Redding before I do anything drastic.

Thanks for any help.
Jason