Ducks, here are the 2 loads I've been using in my 1866 made double. Both are straight of of the Hodgdon manual, using AA hulls/24 grams shot (7/8 oz)

700-X, Remington 209P, CB1100, 16.0 gr, 4,100 psi @ 1150 fps
7625 (if you can find any), Remington 209P, CB1100, 23.5 gr, 3,000 psi @ 1150 fps

Both loads have worked very well, I'm just about out of 7625 so I was forced to switch to 700-X. It works, but doesn't meter as well as 7625.

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