Proof Marks on a Parker

[John Davis]

Thanks David. I'll continue with that assumption until some anglophile comes along and proves differently.

Next question, what does the 3 1/4 tons per square inch translate to in relation to shell/load pressures? I'm once again making an assumption that it's not 6500 psi.

[Drew Hause]

The gun was proved 1954-1989
The mark lower extreme left is the date code
http://www.hallowellco.com/birmingha..._date_code.htm

3 1/4 tons = 9,800 psi = 676 BAR service pressure