740 bars is 10,732.79 psi. That is the service pressure often discussed. So if your gun has a service pressure of 10,700psi shooting shells in the 7-8,000 is a very conservative safety decision.[/quote]

Bullseye! That margin of safety even covers some (relatively moderate) increase in pressure from firing a 2 3/4" shell in a 2 1/2" chamber.