Didn't want to walk on Mark's thread about acquiring a 10g, but the issue of 'Pigeon Gun' weight came up and this is interesting.
At the Riverton Handicap March 8, 1895
http://www.la84foundation.org/SportsLibrary/SportingLife/1895/VOL_24_NO_25/SL2425015.pdf"It may be interesting to some to note the guns and loads used, and we give it below. It was a lamentable fact that of the 15 guns used only one American make was represented. This was a special pigeon gun of the Parker Brothers' manufacture, and was a beautiful weapon in every way, and was owned by Mr. Post, whose score of 93 on a hard lot of birds did not show that the shooting power was lacking.
All the guns were 12 gauge, and it was noticeable that not a full pistol-grip stock was among the number, and most of them were the straight-grip "pigeon gun" model, nine being of this description, and six of the half-grip style. All were of the hammerless pattern excepting two; Mr. Welch and Mr. Robbing using hammerguns."
Following is the make of guns and loads used:
Capt. A.W. Money - Greener, 7 1/2 pounds.
George Work - Purdy, 7 1/2 pounds.
Post - Parker pigeon gun (AAH introduced in 1894)), 7 11-16 pounds.
Jim Jones - Scott, 7 3-16 pounds.
John B. Ellison - Scott, 7 1/4 pounds.
Fred Moore - Purdey, 7 7-16 pounds.
Leonard - Westley Richards, 7 1/2 pounds.
Mott - Crown grade Greener, 7 2-16 pounds.
J.S. Robbins - Greener hammer gun, 7 1/2 pounds.
R. Welch - Purdey hammer gun, 7 1/2 pounds
Downing - Scott, 7 6-16 pounds.
J.K. Palmer – Francotte, 7 1/2 pounds.
Edwards - Scott Premier, 7 pounds.
J. Wolstencroft - Greener, 6 15-16 pounds.
Eckert - Scott Premier, 7 1/4 pounds.
Shells were 45 - 49 grains / 3 1/4 - 3 1/2 drams smokeless powder and 1 1/4 oz.
Capt. Money (2nd in the 1894 GAH) and George Work (3rd in the 1893 GAH) tied at 94 killed.
In 1898, guns used for Live Birds had to weigh
less than 8 pounds.
http://www.la84foundation.org/SportsLibrary/SportingLife/1898/VOL_30_NO_24/SL3024020.pdfJohn L. Lequin. secretary of the Interstate Association, writes us under date of Feb. 25 1898 as follows:
"We have received inquiries from most all directions recently from a number of shooters who are probably desirous of entering the Grand American Handicap next month, concerning the weight of guns, and whether the handhold and recoil pad will be counted as a part of the gun when weighed. The subject has been placed before the Tournament Committee of the association, which committee has decided that the guns will be weighed
naked. 
Kindly note, and make this public through your paper at your earliest opportunity and greatly oblige."
The
Baker Gun Quarterly, Volume 5, No. 3, May 1900 had an article on the weight of Trap/Pigeon guns used by Capt. A.W. Money (8 pounds - Money used a Greener, Smith, and Parker), C.W. Budd (7 pounds 14 ounce Parker), H.D. Bates (7 pounds 13 ounces), R.O. Heikes (7 pounds 15 ounce Parker but after the GAH at Live Birds he went back to his Remington hammerless and won the 1st GAH at Targets), J.S. Fanning (7 pounds 15 ounce Smith), W.R. Crosby (7 pounds 12 ounce Baker), and Col. A.G. Courtney (7 pounds 14 ounce Remington CEO).