DUE FEB 2021 MONSTER 6mmARC Barrels

[Lemonaid]

Here is a data comparison between 6mm arc and 6ppc and 6.5 grendel.

6 arc-------------------------------6 ppc--------------------Difference---------------
Case length 1.490---------------1.5032------------------.0132 longer for ppc
Base to neck-1.2558------------1.2205------------------.0353 longer for arc
Base to shoulder 1.207---------1.0748------------------.1322 longer for arc
30 degree shoulder--------------30 degree shoulder---
Shoulder diameter-.4301-------.4299--------------------.0002 bigger for arc
Neck outside diameter .274----.2618--------------------.0122 bigger for arc
Neck length--.2342--------------.2827--------------------.0485 longer for ppc
Max coal 2.260-------------------2.1929 -----------------.0671 longer for arc
Neck base to max oal-1.0042----.9724-------------------.0318 longer for arc


6 arc--------------------------------6.5 grendel--------------Difference------------------
case lenth 1.490-------------------1.520--------------------.030 longer for grendel
Base to neck---1.2558------------1.280--------------------.0242 longer for grendel
base to shoulder 1.207------------1.1456--------------------.0164 longer for arc
30 degree shoulder-----------------30 degree shoulder----
Shoulder diameter-.4301----------.430----------------------.0001 bigger for arc
Neck O.D.---.274------------------.293-----------------------(.243 vs .264 )
neck length--.2342-----------------.235-----------------------.0008 longer for grendel
neck base to max oal-1.0042-----.980-----------------------.0242 longer for arc

The neck base to max oal is a key one, that is a general max bullet length before intruding into the case body.
If someone has case data for the 6mm AR, or other variants it would be great if you could post them here.