Case Neck Thickness 300/221 Fireball

[mosigdude]

I am between .3295 and .3300 with the few dummy rounds that I assembled, so hopefully I'm good. I'll do a casting on my chamber when it gets in just to make sure.

Now on to part 2:
I'm seeing several variations in the listed max case length, the longest being 1.400". I did an initial trim on my brass at 1.390" but can always go shorter if necessary. What is the "norm" trim-to length that most are using?