doubleriflejack, I have seen many older double rifle actions bent, but none cracked. I believe the older doubles, especially the black powder, and nitro for black ones were made of softer steel, and when the smokeless powders came out no regard to the rifle’s strength was paid. Even the nitro-proofed doubles made in the 1900-1910 era have been ruined by overloads in this way.

The rifle has a tendency to “open” when fired even with proper loads, but if the load is proper the bar can bend a tiny amount, but recover to it’s original position after the pressure spike. If the bar bends more than the elastic properties of the steel, then the bar doesn’t return to it’s original position, and the rifle is now off face. This is the most rare, and most serious off face condition, of the two causes of off face condition.

The most common is not caused by shooting at all, but is caused by the owner’s poor care of the rifle’s mating surfaces. This is caused by wear on the face of the hook, and the hinge pin, and the sides of the lumps. This allows the barrels to move forward, away from the face of the standing breech. Wear on the draw on the sides of the lumps allows twist as one barrel is fired. All microscopically, but enough to make the off face condition apparent in case warping, and the feel of looseness, and will get progressively worse if not fixed!

The “doll’shead”, and the so-called “greener cross-bolt”, if properly fitted, and properly cared for will help in avoiding this tendency to open on firing. Side clips are also a plus in respect to twisting. The most “at risk” actions are the ones with no side clips, or third fastener like the cross-bolt, or doll’s-head. Some of the hidden third fasteners are useless, especially on the cheaper rifles. The “screw-grip” third fastener is a good one if properly fitted by the maker, but if it is not in conjunction with a doll’s head and the hook has not been well cared for it allows the steel to flex forward, but blocks upward rotation (opening) around the hinge pin. However if the screw grip fastener is in a doll’s head both types of movement are modified.

I would say the in the new double rifles, if the mating surfaces are properly lubricated and the loads are not hot-rodded the rifle will handle any proper load the rifle was chambered for by the maker. There is some worry about some of the older rifles, as to the quality of the steel, so that the owner must be very careful about how he cleans, and lubes the rifle, and very careful about the loads, and bullet types he uses in the older rifles. Some bullets will cause very high spikes in chamber pressure, and reverse thrust, both detrimental to older rifles.

Most failures in double rifles from pressure cause the barrel walls to go, not cause off face condition. This type damage is limited to chamber pressure, or spikes in pressure, but is sometimes because of the type of bullet being used! READ MONOLITHIC SOLIDS!

All in all, if a double rifle uses a load that is proper for it, and the care is proper, most double rifles will outlast you, and your great grand children. All this is long winded way of saying if the owner does his care, and feeding properly, he doesn't have to worry about his rifle coming off face anytime soon!