Short and simple store is as follows. The maximum back-thrust on the action face would be akin to the bore area times the maximum pressure. Assume pi X (0.729/2)**2 X 10,000 psi = 0.4172 X 10,000 = 4,172 force pounds. The hook-pin contact on a typical W&S BLE measured about 90% of a 0.500" hinge pin and 0.350" wide hook. Circumference of the pin is pi times diameter = 3.14 X 0.500 = 1.57". The hook bares on 90% of the pin, so the effective bearing length is 1.413". The bearing area then is length times width = 1.413" X 0.350" = 0.495 square inches. Assuming equal pressure distribution (not really valid, but OK for this kind of swag), 4,172#/ 0.495" = 8,428 psi. That is well below the working strength of typical soft, low carbon steel. Nothing of the hook or pin is likely to yield! If a gun is worn off-face, the hook and pin go into a battering mode and that is a different story altogether.
If, the concern is wear, then we have to have a working idea of the action flex as wear requires relative motion. Clearly, there is little motion from firing. However, there is relatively a lot of motion when the barrel is cycled open and closed. Modern high pressure lubes will handle the above pressures nicely. However, grit will infect and taint the lube such that it will act as a grinding agent. Clean modern lube is, IMO, the key to longivity of gun bearing surfaces.
Questions, comments? As always, check my math and logic, please.
DDA
