Gamebore shells follow CIP proof standards. For the 12 and 16ga, that would be a max service pressure of about 10,700 psi, compared to our American SAAMI service pressure max of 11,500 psi. Service pressure increased about 500-1,000 psi when American gun and ammo makers switched from the older, short shells to the 2 3/4" standard for 12-16-20, in the 1920's and 30's. So CIP loads in short hulls should be very similar to the loads which your Fox was built to handle. The only issue with the Gamebores is that they're field loads, not target loads. You can reduce pressure (and recoil) significantly by reloading. But for hunting, I've used the Gamebores in a number of short-chambered Brit and European 16's, and they're a good choice.
Last edited by L. Brown; 07/28/11 06:59 AM.