I think it was Dr. Drew who found some articles from a A.W. DuBray (aka Goucho) about hunting on his tour of the southeast using a Parker Bros. 16-gauge with 2 7/8-inch shells. I found a similar articles from the 16 March 1901,
Sporting Life about his snipe hunting near Beaumont, Texas, using a 3-inch 20-gauge.
Over my years of watching sporting collectibles auctions, I've seen a goodly number of boxes of vintage 3-inch shells in 12-, 16- and 20-gauge and a lesser number of boxes of 2 7/8-inch shells in 12- and 20-gauge but I've yet to see a box of 2 7/8-inch 16-gauge shells. The period ammo catalogs did list them.
ARROW 12-gauge 2 7-8 inch 01.jpg
ARROW 20-gauge, 2 7-8 inch 01a.jpg