On my first try casting bullets for my new revolver, being eager to get started i mixed up a couple of pounds of fishing weights, a pewter knick-knack, and about 10 pounds of magnum birdshot. The mold size was 513-450 from Accurate molds, my bullets weighed anywhere between 440 to 445 grains. I used non scientific methods of testing the bullets by smashing one in my vise and smashing another with a sledge hammer. The lead held together and did not seem brittle until i had it pretty flat. compared to a fishing weight, the bullets seemed harder.
I loaded some up with a starting load of 2400 and just going by the recipe figure they would go a little less than 1000fps. I went out into a burned area of the pasture and tested the bullets on dead cedars, they would go clean through a six inch trunk but stopped in the 8 inch trunks, but what amazed me was the bullets, after going through 6 inches of wood, were almost reloadable. The bullets swagged down some, about 20 thousands and lost a few grains. I was really pleased in how they held together. I can't replicated my mixture of alloy, maybe I'll take notes next time.