Hi again Harrison E,
Being a sissy and all, the .500 NE is about as much fun as I can stand.
Once I fired two rounds from a .600 NE and although the recoil was not as bad as I had expected, it was more than I am willing to put up with (plus the rifle itself was too heavy for me to carry all day long and still be quick with it).
But the .500 in a double of minimum 11 pounds to maximum 12 pounds, is tolerable in recoil (provided it fits you well of course).
Once I fired a custom made .500 made on a Chapuis or Verney Carron action, by Evo-Rifle in Bird Idaho, as I recall.
It had 20 inch barrels and seemed about 2 or 3, (perhaps more) pounds too light for that caliber.
Firing it felt like what I would imagine it's like to be hit by a car.
Also, I have fired a proper weight, Pre-War English .500 NE double and it felt close to the same as a similar quality .470 I have fired felt, IMO - within my recoil tolerance level in other words.
Regarding what rifle I would recommend for this caliber, if money is no object, I feel the best of the best is the Westley Richards Droplock Model, but there are other makers in the high price range that build some likewise staggeringly wonderful doubles to order.
If you wish to keep the price below $20,000.US, then have a look at the Meym PH Model, or the slightly more fancy 88B Model.
Last time I looked at:
www.champlinarms.com , they had an 88B in .500 with ejectors (I prefer ejectors), among their used rifle section.
Cheers,
Velo Dog.