What do you think ?
A good 7grains of powder, a 6grain sabot + a 40grain 22 bullet would be easy to get past 1900fps from a 4" Parabellum.
Single shot only but i might try some day
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Sabot is the french for wooden clog and sabotage was the 1700's workers way of having a break.
The first things to get automated with the advent of steam, was spinning machines and looms. Now suddenly 12 hours of work without a break, so workers threw a clog in the looms and got a little break as machinery got fixed.