.50 bp Pistol Pressures and loads (Also: Test firing procedures?)

[Modular_Dingus]

I'm building a bp pistol from scratch. To make generous safety margins I need to know the pressure data for light, moderate and heavy loads. Also, Is it worth using calipers to measure any bulge after initial remote fires? I doubt there will really be any difference because I've purposely made it meatier than needed but I'd like to know what you guys do for the first shots from a scratch build.

Thanks

 

[Rat]

What kind of barrel and breech are you using? I once made a pistol from the end of a .58 caliber rifle barrel (Miroku Zoauve) and a handmade breechplug. I just kept the loads under 50 grains. Did not do any proof loads. That was years ago, I think now I would proof such a project, and measure for any expansion. I would use a very high quality micrometer to take measurements, and yes, that would be a good, worthwhile idea. If you did a good job on the breech, and are using a heavy barrel, there should not be a problem with even heavy loads, other than excessive recoil.