Before you guys brought in the idea of shrinkage, I made a template of the smallest pouch and cut out a similar piece of leather. It´s really small, so I decided to attach short single cords to it and tried 5 throws with stones of max. 4.5 cm length. 4 of 5 stones fell out. I tried 2x greek overhead, 2x sidearm and 1x (modified) apache style. Only 1 sidearm throw worked, and the power was more than bad. But I´m not a very skilled slinger and I think the ammo was too big. Maybe one of you will have more success. Considering the shrinking of leather things would change and I´d sling with a pouch size that`s more similar to the one I`m used to.
Small pouches (better: small ammo) could maybe have been used by peasants to protect the harvest from groups of small birds on the field without damaging the plants as it would have happened with big stones. Or maybe people threw small stones with short-corded slings inside in a stable to birds, mice, rats that were sitting under the roof, too high to reach them. In this case smaller stones would have done their work, again without causing too much collateral damage.
But this are only personal speculations (I´m also academic
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