Sherman Bell uses some pretty sophisticated pressure measuring equipment. I'm not sure that Burrard measured anything. I'm not sure, either, of Larry Brown's statement that some of the pressure differences in light loads in two different chamber lengths with 2 3/4" shells exceeded 1000 pounds per square inch. I'll have to read the article again to confirm, but the testing and the article's conclusions lead me to be very comfortable shooting 2 3/4" light loads in my 2 1/2" chambered British game guns.