Be carefull using wheel weights. Good way to ruin an airgun barrel. Zinc wheel weights will melt into the lead if you get it hot enough! A guy on another forum ruined his Texan using wheel wieght alloy.
I don't know of any airgunners that use anything but lead/tin alloys, because they are too hard.... This both increases the chambering effort (or you have to size them smaller), and may increase the bore drag.... and certainly affects the expansion.... Softer alloys expand at lower velocities, in the exact same bullet.... The BHN of pure lead is about 5, if you use 40:1 (2.5% tin) that is about BHN 7, Clip-on Wheel Weights are typically around BHN 11-12 (but some are much harder), and 10% tin/lead is about the same.... I don't know anyone who goes harder than BHN 12 in airguns.... If your wheel weights are harder than 2.5% Antimony, they are hard ones.... If you want good information about bullet alloys, read this page.... http://www.lasc.us/castbulletalloy.htmBob
I'm getting the hang of it now. I made batch of 80 with no major rejects. They did have some smudging on the base where I don't think I let them cool quite enough before cutting the sprue but otherwise they came out great.
Quote from: aceflier on March 18, 2017, 07:23:53 PMBe carefull using wheel weights. Good way to ruin an airgun barrel. Zinc wheel weights will melt into the lead if you get it hot enough! A guy on another forum ruined his Texan using wheel wieght alloy.Thanks for the link. So it seems that the issue with the zinc or the otherwise hard ww bullets is it caused the bullet to jam. I could see that happening if someone forced them in.
Zinc doesn't mess up the barrel. Bullets become to hard and get stuck in the bore. Then you ruin the barrel trying to beat it out of the barrel. Better to heat the barrel until it melts then push it out.