Good evening,
I usually load 52gr SMK or A-Max but have recently been trying the Hornady 40gr V-Max (with N133) and am finding considerable differences in the COAL suggested by the various reloading manuals and powder/bullet manufacturers.

Vihtavuori: 2.075"
Lee: 2.165"
Sierra: 2.175"
Hornady: 2.2"
Lyman: 2.215"
Sierra 2.25"

I'm not convinced that the Vihtavuori figure can be correct as it is so much shorter than all the others and would, I think, result in a very compressed load.

Any thoughts please? I have been loading to 2.23" with reasonable results, but cannot go any lower as there is insufficient adjustment on the Lee seating die. I could turn up a slightly different insert for the seating die to get me to shorter COAL but am wondering whether there's any point.

Questions really are (a) whether the Vihtavuori data is incorrect, and (b) whether there's any benefit to seating to give COAL of 2.2" or less with a 40gr bullet, in particular 40gr V-Max?