Steve: How did you come up with 48,500 psi for a pressure? If that is with LilGun powder I don't think you can get enough powder in a 22 Hornet or K Hornet to reach that pressure. My experience with LilGun is that it is bulky but a low pressure powder. Hodgdon data shows 45 grain Hornady bullet 12 grains of Lil Gun at 2662 fps at a pressure of 26,500 CUP. 13 grains shows 2787 fps at 31,600 CUP. Lots of variables there (CUP vs. PSI, thick neck, etc.) but 6,900 pressure difference seems a bit much.
When discussing maximum Contender pressure, regarding the 308 Bellm Mike Bellm told me to keep pressure around a maximum of 40,000 in the Contender action. Bellm felt that the G2 action was a bit stronger but J. D. Jones told me the strengthened receiver walls of the G2 action did not help much. The .444 Marlin case head is .514, the 223 is .378 and the 22 Hornet is .350. Since the Contender is chambered in the .223 Remington at about 50,000 psi and .378 case head, if you did get a pressure of 48,500 at .350 you probably did not stretch the frame but that is conjecture on my part.
