Terry: the long version of "what load should I use" is toward the bottom here
https://docs.google.com/document/d/1ZIo0y746UsSRZIgRuuxwAbZjSBHitO_EanvwLYc-kGA/edit

The medium version is "loads for which the gun was designed" with a recognition that both pressure and recoil (load weight and fps) matter, and the mechanical lock up and wood are now > 100 years old.

The short version is (after the gun has been evaluated by a double gun specialist) pick a 1 oz load at 1200 fps or less and be happy smile

BTW: nice gun that should give you lots of pleasure, but Bro. Rocketman is being generous. The market today for even lightly used vintage "field grade" American and Belgian 12g doubles is very poor, and not likely to improve.

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