Hey, Y'all,
4seventy, could I ask the brand and type, also the size (12, 16, 20?)that your double was built on? I personally have a huge preference for sidelocks, preferably the grand old L. C. Smith, but they on average have a little less wood in the wrist and around the lock plates to take up the back-thrust. Is this a concern, or am I an old lady? Is your double a .470, as your handle would suggest, or do you own more than one double? How about my selection of calibers? I envision either a .470, or the .45-120 (3" case, same powder capacity as the now-popular .458 Express, which is a 3" 458-style Magnum case, except with the same rim as the .45-70). Hulls for the .45-120 are readily available, and relatively speaking, dirt cheap. You should be able to crank out 2200-2300 fps with a 500 gr. Hornie Solid in this length case while keeping pressure 'way down there. Whacha think, guys? Everyone's opinion is welcome and valued.

P.S. If someone could come up with the name and author of the book that Mickey mentioned, I'd certainly try to secure a copy! And Thanks in advance.

"When in Doubt, Use More Gun!!!"