Update. I ran a stress analysis for a typical 12 bore chamber with an inside radius of 0.405", outside radius of 0.600", and a radius within the wall of 0.500" at a pressure of 10,000 psi. The hoop stress is 20,400 psi, the axial stress is 8370 psi, and the radial stress (within the wall) is -3680 psi. All the above are well within the working stress levels for low carbon steel.

Gotta think about these numbers. What are they going to tell us?? Knowledge and/or opinions welcome.

DDA