Shoulder bump with different brass?

[Macropod]

Datums.....

 

[6MMsteve]

Usually the culprit behind different bump lengths is lube on the shoulders. You really only need a little bit of sizing wax on the bottom half of the case. If you start seeing it on the shoulder area when pulling the case from the die youre using too much. I have an old bent pistol rod with a 12ga cleaning mop on it- when i see the lube creeping up on the case ill mist that mop with carb cleaner and run it in the die to clean it up. Any lube besides imperial will at best cause bumping inconsistency and at worst a stuck case.

imperial always for me nuttin else

 

[6MMsteve]

where is Guffer at

 

[JFrank]

Myself I've been guilty of not cleaning my Dies enough, as Dusty points out inconsistencies are early indications of excess lube.

Another thought is there are some close measurements in regards to the case head and the shell holder. I just measured both and all are closer than I would like for working with different brands of brass.

shell holder;
deck height .123
diameter of chamfer on shell holder top face .530 ( it's early and just used old eyes and caliper)

case head;
face to bottom of belt .125
belt .532

With your Die installed ( no brass)
Put a feeler gauge under your shell holder on full ram extension and take a measurement.