The 1933 edition of ”Smokeless Shotgun Powders” by Wallace Coxe and E.I. du Pont de Nemours & Co. reported the LUP pressure for
1 1/4 oz. 3 Dram Eq. of DuPont Bulk Smokeless at 9,600. Modern piezoelectric pressure would be about 10% higher.
In the 1928 edition, Coxe reported
3 1/2 Dram Eq. 1 1/4 oz. loads:
DuPont Bulk Smokeless powder - 11,700 psi
Schultze Bulk Smokeless powder - 11,800 psi
28 grains of Ballistite - 12,600 psi
Note: Pressures are beyond the modern SAAMI recommendation for 2 3/4" 12g of 11,500 psi.
DuPont Bulk, Schultze, "E.C." (all bulk) and Ballistite and Infallible (both Dense) were available in most c. 1906 shells, and 3 1/2 Dram Eq. with 1 1/4 oz. shot would be a common "Pigeon Load".
