Just a thought here fer fun, I use up unknown, strange lead that I am not sure of in a 0.451 ball mould. And why do you ask, slingshot! Wish I'd had a few 25 lb shot bags of these 35 years ago. Would a beat tryin' ta find round rocks and they are wicked comin' out of these modern slingshots.
Just a FYI in case ya ain't thought of it 25 years ago like I did.