While the 2 9/16-inch was the "standard" length for 16-gauge shells here in North America up into the 1930s, our ammunition companies offered 2 3/4-, 2 7/8- & 3-inch 16-gauge shells. The Remington era specification sheet show a 2 5/8-inch chamber depth for 2 3/4-inch shells.
Remington Specification Sheet GHE, 16-gauge highlighted.jpg
The 1927 Peters Cartridge Co. catalog shows they would put up their High Velocity loads in any length shell --
HIGH VELOCITY loads 1927, 16-gauge highlighted.jpg