Due to inability to find the powders I would like to use I worked up a load for powder I had sitting: Herco. Posting results in case it might be helpful for someone that can find it.
Fiocchi Hulls - Cut to 2.60" (OK so not exactly 2 1/2", but that's what my cutter was set to)
Fiocchi Primers - whatever primers come in Fiocchi primed hulls - I _ASSUME_ they are Fio616, but I don't know because the bags are not marked.
Powder - Herco, an old can I had laying around. I tried 22, 22.6, and 23.0 grains. The lower charge weights did not have consistent enough velocity for my liking, and I am posting the 23.0 grain load.
Wad - SG16
Shot - 420 grains (OK - not exactly 1 oz either!!) of lead 7 1/2 chilled.
Overshot card
Crimp - Roll crimped with PRI roll crimp tool to +/- 2.4"
Results per pressure testing at Precision Reloading:
Average Velocity 1,273 fps Standard Deviation: 19 fps Extreme Spread: 52 fps
Average Pressure: 6,797 psi Standard Deviation: 337 psi Extreme Spread: 810 psi
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Thoughts: This roll crimp load required 1/2 grain more than published fold crimp loads to achieve published velocity, but did so about 1,500 psi less than loads as published by Ballistic Products
I was not happy with the extreme spreads of lower charge levels, but I am confident this load is still safe in my 1920's Belgium SxS
Time will tell whether this powder might result in "bloopers" if re-tested in cold weather. Hopefully not, because ammo and powder is in short supply.
Hope that helps. You are responsible for your own loads, and load development. Check loads against published data. I am not responsible for you hurting yourself, this load appears safe in MY gun.
