From about 1870 paper and brass case 10 gauge shells were 2 7/8".
Lighter loads were available, but the standard load was 1 1/4 oz. with 4 drams black powder.

"Outing: Sport, Adventure, Travel, Fiction", 1889
Al Bandle, of Cincinnati, on Christmas Day, 1888 defeated the famous shot, Captain A. H. Bogardus, by killing 100 live birds straight to the Captain's equally remarkable record of 95. Bogardus shot a 12-gauge L.C. Smith gun, hammerless, 7 lbs. 12 oz. weight and shot 4 drams American Wood powder in his first barrel, 1 1/4 oz. No. 8 shot in first and 1 1/4 oz. No. 7 in second, backed up with 4 1/4 drams Laflin and Rand Orange Lightning powder.
Bandle shot the same make of gun, 10 gauge, and used, first barrel, 4 drams Wood powder, second, 4 drams Laflin and Rand “F.F.F. extra” powder, No. 7 shot.