Proof Pressure Questions?

[ohiochuck]

What are/were the proof pressures and the service pressures for German firearms (shotguns & drillings) that were nitro proofed for 12 bore firearms with 2.5 inch chambers and the proof pressures for 2.75 inch chambered 12 bore firearms?
Is the proof presures the same or different for drillings (rifle barrels) with nitro proof?
Thanks!
Jim

[sharps4590]

Jim..

I can't tell you what the actual pressures are for 12 bore 2 1/2 vs. 2 3/4 loads, I simply don't know Reference the rifle barrel on the drilling I'm a bit confused as to your question. If it is are the rifle and shotgun barrels proved at the same pressure, no. Rifles are proved considerably higher. If it is are drilling barrels proved at the same pressure as bolt guns I would have to assume yes given identical cartridges. That is to say that a bolt gun in 375 H&H is proved at a higher pressure than a break action firearm in 375 Flanged or Rimmed. Very similar cartridges but not identical.