Thanks Robin. I wear a strap-on pad when I’m working up heavy hunting loads in my 50 cal rifles and it really helps. At the moment, I’m looking at a 54 cal rifle for Table, chunk, cross sticks, etc. and got to wondering if that pad would be a violation. It’s a 38” bbl, and (I’m told..) weighs 12 pounds.
Seeing some padding inside a shooting shirt might be a good alternative and might be enough in a rifle that heavy, even with stout loads.

I might not end up with the rifle afterall. The fellow who has it took it in a trade. He literally just got it (day before yesterday) and has put it up for sale immediately without firing a shot. He's leaving for Friendship next week, and will be putting it in the Gunmaker's Hall for sale when he gets there. I told him if he doesn't get it sold there, I'll take a serious look at it when he gets home with it. At the moment, I just don't have time to go through a serious evaluation of both the rifle and get a handle on how much I may or may not enjoy the types of competitions such a piece is built for. Down here there's no active table, chunk, cross-sticks or bench shooters I'm aware of to shoot with. 
We'll see.