Sorry meant Rockwell Hardness number, after aux-treating number increased to 52 with no distortion of the frame and the pin still in place. This metallurgist has a lot of experience with heat treating gun frames and said he believes the frame capable of handling well over 100000 psi after the treatment. I keep my loads around 25000psi, just to be on the safe side. I have heard that Searcy used to heat treat his Browning framed guns to a RN of 37, then have them color-case hardened.

Side note: According to the barrel maker, their steel will take over 120000psi radial and bulge before rupturing, which allows the gases to escape around the bullet and out the muzzle. For what its worth.

Of course your mileage may vary. When in doubt have the frame tested and heat treated, its only about $200.00 to do this and it will give you peace of mind.

BS-