You do in fact have a great English double rifle! Well, at least now I can end my search. I would have sworn that it was proofed for 70 grains of cord, I guess as the saying goes my memory is great, it just does not last a long time!
As far as loads, JJ is the one who worked up a load for the rifle. I will have to dig back in old data to see what I have, I would think JJ might have a record of what he worked up, would have been in 1999 or around 2000 as I hunted in Zim in 2001. Fairly certain the load he settled on was IMR 4831, with F215 primers, would hate to say the amount of 4831 as you can see my memory on cord was not correct. Of course the bullets were 400 gr. Woodleighs. If you talk to JJ mention my name to him, Dennis Toews. He might have the records based on name more than serial number, don't know for sure though. I know him fairly well and make frequent trips to Enid, as my parents are still living there, as a matter of fact heading there this weekend. The double rifle belonged to Bill Renie originally, who worked for many years at Champlin as one of the "smiths" before passing away at a young age. Bill was a barrel freik so anything which had a great bore on the inside got his attention, did'nt matter what the outside looked like. Before Africa the rifle took quite a few Jack Rabbits,[ great way to practice,] in Zim took a very good Buff, Impala, and Waterbuck. Anyway, glad the rifle found a good home!!