It is worth noting that turn-of-the-century Pigeon Guns mostly had straight stocks, which were occasionally referred to as a "Pigeon Stock".
1894 ad for the Smith Pigeon Gun
Things started changing after Fred Gilbert won both the First DuPont Grand Smokeless Championship Handicap Live-bird Tournament October 1895 and the “E.C.” Powder Co. (Target) Tournament May 1896 with a Smith. The “Fred Gilbert Specifications” were for a drop at comb of 1 3/8 inches; at the heel, 2 inches; length from trigger to heel, 14 1/4 inches; trigger to toe 14 1/2 inches; and trigger to center of butt 14 inches; with a
full pistol grip and 30-inch full choke barrels; very "modern" dimensions.
Guns, shotshells and loads at the 1895 DuPont shoot
Dimensions of the 1897 Tournament grade; DAC 1 3/4” & DAH 1 13/16”; from
Sporting Life June 26 1909
Jay Graham won Gold at the 1912 Olympic games with a straight stock Remington Pump
As late as this 1923 ad Trap models still had straight stocks
