At the risk of sounding like Forest Gump, if the Jones action is so strong would a 500BPE take the pressure of a 500NE???
Hi Norfolk Shooter,
Excellent question, thanks for asking it.
The Jones screw thread / under lever breach locking design is extremely strong for hinge frame type doubles and single shots.
As Red Leg pointed out, they tend to not shoot themselves off face / loose in the hinge, etc.
The .500 NE would be no problem for it, in a modern high quality firearm.
Firing full nitro loads in any Black Powder firearm is at the least risking your expensive weapon and at worst it is risking your eyesight, if not your life, because if a chamber bursts, (they generally are quite a bit thinner than their corresponding nitro descendants) the excitement will be close to your face.
Definitely not worth the risk.
For a bit more money you can just buy a nitro double in the first place.
Fact is, with today's steels and heat treating methods, the Jones patent would probably hold up to as much chamber pressure and recoil as any mortal, even Matt85, could possibly stand against their shoulder.
However stout that it is, as Red Leg also pointed out, this type of lockup is slower to open and close than the more popular top lever.
So this, combined with obvious higher cost of manufacturing, no doubt is why you don't see them on today's hinge frame rifles or shotguns.
While I'm on the "breach locking design rant":
Probably the strongest breach system for doubles would be the falling block.
It is very common on single shots (such as the Ruger, Dakota Model 10, antique Farquarsons and others) but seldom seen on doubles for some reason.
They have been made but not many, as far as I can tell.
It is stronger in lockup (in terms of resisting wear from high chamber pressure and heavy recoil), than same caliber bolt actions generally are (the falling block's extractors or ejectors are typically not very robust though).
The tilting block found on Martini, Peabody and some other single shots (as well as the Savage Model 99 lever action repeater) is another extremely strong breach design but, I do not know of any double having been built with this design.
It would add length to the rifle or shotgun, whereas the hinge frame adds virtually nothing to length and the falling block action adds very little to over-all length.
Sorry for the length and tedium of my blathering here.
Blah, blah, blah, out,
Velo Dog.