Didn't want to clutter the SBT thread. It is my opinion (meaning little) that the move to a full pistol (rather than straight or POW) grips for double guns started about 1895.

Fred Gilbert (1865-1928) was one of the world’s best known shooters from 1895-1915 and used a L.C. Smith to win the DuPont World’s Pigeon Shooting Championship in 1895 and the "E. C." Inanimate Target Championship Cup in 1896.
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.

In Feb. 1898, C.W. Budd received on consignment a Parker $400 AAH Pigeon Gun SN 87449 with 30" Whitworth barrels F/F and 2 7/8 " chambers. LOP was 14"; and DAH 2 1/4" with a pistol grip stock and no safety. It weighed 7# 12 oz.

November 23, 1901, The Sportsmen’s Review, in an article written by “Gaucho” entitled, “A Few Remarks on Some Celebrated Guns,” Capt. du Bray lists some prominent Parker shooters and the guns they used. Courtesy of John Davis.
Straight - 19; Pistol - 8; 1/2 - 5

Name --- Barrel Length -- Weight -- DAC -- DAH -- Stock Length -- Grip
W. E. Beesom -- Parker -- 32" -- 7' 15" -- 1 7/16 -- 2 1/4 -- 14 1/2 -- St.
W. L. Boyd -- Parker -- 32" -- 7' 14" – 1 1/2 -- 2 1/8 -- 14 1/8 – St.
C. W. Budd -- Parker -- 30" -- 7' 15" -- 1 1/2 -- 2 -- 14 -- PW
P. W. H. Colquitt -- Parker -- 30" -- 7 12"-- 1 1/4 -- 2 1/4 -- 14 3/4 -- St.
V. C. Dagan -- Parker -- 30" -- 8' -- 1 3/8 -- 3 -- 14 1/2 -- P.
O. R. Dickey -- Parker -- 30" -- 7' 14" -- 1 5/8 -- 2 1/4 -- 14 -- St.
E. E. Ellis -- Parker -- 32" -- 8' -- 1 5/8 -- 2 5/8 -- 14 1/2 -- P.
F. C. Etheridge -- Parker -- 30" -- 7' 6" -- 2 1/8 -- 3 1/8 -- 14 -- 1/2 P.
A. H. Frank -- Parker -- 30" – 7' 12" -- 1 1/8 -- 2 3/8 -- 14 -- St.
Fred Gilbert -- Parker -- 30" -- 7' 14" -- 1 3/8 -- 2 -- 14 1/4 -- P.
W. A. Hammond -- Parker -- 32" -- 7' 15" -- 1 5/8 – 2 3/8 -- 14 3/4 -- St.
Jno. W. Harrison -- Parker -- 28" -- 6' -- 1 1/2 -- 2 1/2 -- 14 -- P.
Sam Hutchings -- Parker -- 32" -- 7' 14" -- 1 1/2 -- 2 1/2 -- 14 1/2 -- St.
J. F. Jordan -- Parker -- 26" -- 5 3/4 -- 2 -- 3 -- 14 -- St.
H. J. Lyons -- Parker -- 30" -- 7' 10" -- 1 1/4 -- 1 7/8 -- 14 1/8 -- St.
Geo. S. McAlpin -- Parker -- -- 7' 6" -- 1 1/4 -- 1 3/4 -- 14 1/2 -- St.
J. R. Malone -- Parker -- 30" -- 7' 15"-- 1 1/2 – 2 -- 15 -- St.
R. R. Merrill -- Parker -- 32" -- 7' 14" -- 1 5/8 -- 2 5/8 -- 14 5/8 -- 1/2 P.
F. S. Parmelee -- Parker -- 32" -- 7' 12" -- 1 1/2 -- 2 -- 14 1/2 -- P.
C. M. Powers -- Parker -- 32" -- 7' 15" -- 1 1/8 -- 2 1/4 -- 14 3/8 -- St.
W. C. Rawson -- Parker -- 32" -- 7' 15" -- 1 3/8 -- 2 -- 14 1/8 -- St.
R. S. Rhoads -- Parker -- 30" -- 7' 15" -- 1 1/8 -- 2 1/8 -- 14 1/2 -- P.
C. E. Robbins -- Parker -- 32" -- 7' 11" -- 1 1/2 -- 2 1/2 -- 14 1/4 -- P.
Frank Simpson -- Parker -- 32" -- 7' 14" -- 1 1/2 -- 2 3/8 -- 14 3/8 -- St.
Franklin Stearns -- Parker -- 32" -- 7' 15" -- 1 1/2 -- 2 1/2 -- 15 -- 1/2 P.
E. H. Tripp -- Parker -- 30" -- 8' -- 1 1/2 -- 2 5/8 -- 14 1/2 -- St.
S. A. Tucker -- Parker -- 30" -- 7' 14" -- 1 1/2 -- 2 -- 14 -- St.
D. A. Upson -- Parker -- 26" -- 7' -- 1 1/4 -- 2 -- 14 1/4 -- 1/2 P.
R. Van Gilder -- Parker -- 27" -- 6" 2' -- 1 5/8 -- 3 1/8 -- 14 1/4 -- St.
Wm. Wagner - Parker -- 30" -- 7" 10' -- 1 1/4 -- 2 1/4 -- 14 --- St.
Dr. F. C. Wilson -- Parker -- 32" -- 7" 10' -- 1 1/2 -- 2 1/4 -- 15 -- St.
Leroy Woodward -- Parker -- 30" -- 7" 13' -- 1 3/8 -- 2 -- 14 1/4 -- P.

However, single barrel repeating shotguns continued to come with a straight grip, including the Winchester 1897 Tournament Grade trap gun introduced in 1909



Model 12 1914



Stevens Repeater 1913






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