Did some shooting today.
The 38 mm steel balls (224 gramms, a solid half pounder) are just amazing. I cut a pouch and a quadruple TB Gold band set, full butterfly, for it. Shot from the Panther, I get 32 m/s - that is 114 Joules of energy, 84 ft-lbs.
7,2 N momentum, twice as much as a .45 ACP! Enough to topple over my steel catchbox.
It takes courage to shoot such a heavy monster from a handheld slingshot. But after a dozen shots, I found my confidence!