.357 SIG vs .38 Super


North Central Texas
Is there a cut-away available of a .357 Sig case with a MP 125 gr. HP or other 125 gr. bullet, that shows how deep the bullet goes into the powder or below the shoulder?
Just trying to figure out how much bullet shank is exposed to the powder.
I can figure it out, just thought someone might have one.
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Residing in New England
Drat you guys and your 357 SIG texts. You tempt me greatly to head down that rabbit hole. For those in the know, do the 357 SIG seating dies apply a roll crimp, or are they taper-crimp only? I don't 'get' why the designers have the caliber headspacing on the case mouth when there is a beautiful shoulder right there to headspace on, like reasonable people hewed to 120 years ago. Tiny necks are a PITA without a roll crimp, IME.
They are taper crimp as they decided to HS off case mouth.

I COMPLETELY agree and set mine to HS off that shoulder. They shoot great and I have zero issues.