Re: 300 wsm coal's?
Rather than guessing:
300 WSM case length = 2.10"
Hornady 208 Grain A-max OAL = 1.532"
"" Bearing surface = 0.555"
"" Nose length = 0.777"
If you keep at least one caliber of bearing surface in the case:
0.555
0.777
Less: 0.300 equals 1.04" of bullet outside the case.
2.100" + 1.04" = 3.14" MAX COAL
Oddly enough, the Seekins SA WSM DBM is set up for a max COAL of 3.14"....
If you have some other bullet in mind like the 220 or 240 SMK, let me know and I can give you numbers for those as well.
Bob