Safariman-I use formula and MBP chart to run pressures,
with chrono. My pressures range between 20,000 and 35,000
psi for the Savage bolt action.It has a 3 lug bolthead,
and pretty strong for a overgrown shotgun bolt action,
and 35,000 is max pressure based on shear rating that
I calculated of the lugs with proper safety margin.The powders are all slow,using the case capacity.Here is pic of case next to regular 12ga shell.ED

[Linked Image]

Ed Hubel