Looking through the record of guns and loads, almost all the competitors used 1 1/4 oz. 3 1/2 Dr. Eq. Bulk Smokeless in < 8# (as required) guns
https://digital.la84.org/digital/col...oll17/id/45661
1 1/4 oz. 3 1/2 Dr. Eq. (1275 fps) in an 8# gun = about 27 ft/lbs free recoil; with Bulk Smokeless pressure about 11,500 psi = the modern SAAMI recommended maximum service pressure
Delicate guns and light loads NOT, and tough shooters who were not (in general) as large as today's men.