I know that this post is 4 years old, but I found some information about this gun.
I just thought if someone ended up with it, they would like to know some of its history.
This gun was used and tested for a article in Sporting Life in 1900.
Gun was tested for velocity and pattern against a 12 gauge Parker.
link to original article:
http://library.la84.org/SportsLibrar.../SL3521013.pdf
Ballistic tests made at Bridgeport, Conn.,
May 3, 1900, over the range and on
chronograph of the Union Metallic Cartridge
Company. Tests made by Mr. Wm. M. Thomas
and his assistant, Mr. Howard D. Hodge.
Parker gun No. 82403, 20 gauge. Length of
barrel, 30 inches. Titantic steel. Both barrels
full choke, chambered for 3-inch cases. Shell
3-inch Smokeless U. M. C., 20 gauge. Powder-
Hazard Blue Ribboa, 2-1/2 drams, say 31 grains.
Shot Tatham's 7/8 of an ounce, No. 7 chilled.
Wads Trap 3/8-inch Express, 3/8 in Black edge
"C" card all 20 gauge.
Velocity in feet 40...........Pattern in 30-inch
yards from muzzle..................Circle.
908.................................194
915.................................223
919.................................237
929.................................191
920.................................202
904.................................211
896.................................222
918.................................226
909.................................214
918.................................214
Average 913.6 ft. s. ............average 213.9 Pellets
Variation 33 ft. s. ...............variation 46 Pellets
.