The Model 1901 was made for the 2 7/8 inch 10-gauge shells, but during the years of its manufacture, the heaviest 10-gauge shells our manufacturers supplied were 4 1/4 drams of bulk smokeless powder or 32-grains of dense smokeless powder pushing 1 1/4 ounce of shot. The progressive burning smokeless powder Super-Ten 2 7/8 inch shell with 1 5/8 ounce of shot didn't come out until 1925 or 6.
The Model 1901 was never intended for loads like these, but many of them have digested their share.