This Remington era gun would have been chambered for 2 3/4 inch shells unless special ordered for something else. SAAMI specs had been in force for a decade when this gun was made. Remington 16-gauge shells at the time this gun was made were the 2 3/4 inch Auto-Express --
16-gauge Auto Express.jpg
the 2 9/16 inch Nitro Express --
16-gauge Nitro-Express 1934 to 39.jpg
The 2 9/16 inch SHUR SHOT --
SHUR SHOT 16-gauge 2 9-16 inch 1 ounce .jpg
Remington led the transition from the 2 9/16 inch 16-gauge shell to the 2 3/4 inch when they introduced their Model 11 and Sportsman autoloaders in 16-gauge in 1931 made for 2 3/4 inch shells. The first 16-gauge guns out of Ilion since the quit their hammerless doubles in 1910. By 1933 their Model 31 pump gun was on the market in 16-gauge also made for 2 3/4 inch shells. Along with these 2 3/4 inch chambered 16-gauge guns Remington introduced their 2 3/4 inch progressive burning powder Auto-Express shell with a 3 1/4 dram equiv. 1 1/8 ounce load. Their 2 9/16 inch progressive burning powder Nitro Express shell carried a 3 dram equiv. 1 1/8 ounce load.