I was looking at Mr. Hause's post about pressures from about 1900. The service charge for a 3 dram load was 5800 psi. My gun was built as a very light game gun (sub 6 lbs in 12 gauge), with 3 dram loads in mind I suspect. Of course it was proved higher, but if that was what it was designed for 150 yrs ago, I figured a safe margin would be to try to stay under 5000 psi. I'm no expert for sure, perhaps I'm being overly cautious

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