So i have bought about a ton of alloy (94% lead, 6% antimony) in 30kg ingots. I am certain the alloy will be hard enough but would I need to throw in some tin for mold fill? If so, I was considering 1%, so 300 grams. This will be for bullets that will be loaded to less than 1200 fps. Will this be good enough or should I go with 2% tin for a proper hardball alloy? Lastly, and I am by no means a math boffin , am I calculating the tin correctly or is there some other arb formula to add metal to an existing alloy?