To Lagopus' point:

Chamber Length 1954 Stamping(in Tons) Service Pressure (in PSI)

2 1/2, 1 1/8 oz, 3 Tons, 8,943 psi

2 3/4, 1 1/4 oz, 3 1/4 Tons, 9,686

3, 1 1/2 oz, 3 1/2 Tons, 10,427

3 Magnum , 4 Tons, 11,913

“I left long before daylight, alone but not lonely.”~Gordon Macquarrie