Ok, here's a 19th century shotgun shell chart (can't actually date it) showing Kynoch shells from the period but since it has pin-fires and center-fires it has to be around 1870:
[Linked Image from jpgbox.com]

Diggory just published an article on cartridges...but he doesn't mention time periods or dates" (and it is somewhat confusing...does 2 1/2" also encompass 3" pigeon loads at the time?)
English guns will have nominal chamberings of 2 1/2”, (note that the actual chamber length may be 2 5/8” or 2 7/8”), 2 3/4” or 3”. The last two normally reserve for wild-fowling guns and guns for live pigeon trap shooting.
https://www.vintageguns.co.uk/magazine/chambers-chokes-and-weights

Above Steve mentions an "LC" in a diamond indicating "long-chamber." I cannot find that symbol anywhere in 19th century proof-marks. I'm sure it must exist...but in 1869? It's not on 15625 or any of the big bore Reilly's from the 19th century. Could someone post an example please. (I am here to learn as always).

Gene

Edit: Lagopus in the pin-fire line states authoritatively that this is like from the 1882 Ely-Kynoch catalog. Well...that's pretty definitive.

Last edited by Argo44; 04/05/21 11:02 PM.
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