Just my take on things, but if I had a vintage American double gun (Parker, Fox, Lefever, LC Smith, Ithaca) made after smokeless powders came into common use and felt the need to limit it to < 6500 psi for fear of blowing up a barrel and injuring myself or someone else, I'd toss the barrels into my neighbor's swamp and part out the gun. If the barrels were that weak I wouldn't ever sell the gun intact or have it passed on and set someone else up for a blow up and serious injury or worse. I’m talking here about pressure, not recoil; they’re not directly related and are so often confused and some even use the terms interchangeably. Again this is just what I’d do in that situation.
