A good summary of guns (and loads) used for Live Birds in the U.S. is here, with the competitors using them
https://docs.google.com/document/d/1D8QkBDo-KIQYk2G8lkE-kHLUybB5NJzBahX_eFKEyuY/edit

March 2, 1894 Riverton vs. Carteret
Fred Hoey - Purdey, 7# 8 oz.
Charles Macalester - Purdey, 7# 5 oz.
Capt. A.W. Money - Greener, 7# 8 oz.
George Work - Purdey, 7# 8 oz.
Edgar Murphy - Parker, 7# 6 oz.
T.S. Dando - Parker, 7# 6 oz.
H.Y. Dolan - Scott, 7# 8 oz.
R.A. Welsh - Churchill, 7# 9 oz.
Guns were limited to 8# and the loads mostly 1 1/4 oz. 3 1/4 - 3 3/4 Dr.Eq. - ouch!

Prior to 1895 the choices were mostly Scott and Greener, with a few Purdey, Smith, and Parker
In 1895, Mr. Will K. Park, Gun Editor for Sporting Life began to aggressively promote American maker's guns in a series of editorials and then Smith and Parker were dominant, with some using Lefever.

Guns, loads and shooters at the 1895 DuPont Live Bird Tournament

[Linked Image from photos.smugmug.com]

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