I have been casting .309, .339, .430 and .512 caliber bullets on and off for several years. I was told that I need to keep any zinc out of the pot. How do I recognize a wheel weight containing zinc? I heard that the shiny looking WW were more likely to contain zinc. Any suggestions?

The bullets cast by my CBE mold will tumble 90 degrees with-in 25 yards unless I use a gas check and size to .510 for use in a 510 whisper. I am thinking I can improve the performance of the .339 NEI cast bullets if I use a gas check. The problem is the Hornady gas checks are very thin, only 0.010". The 30 and 44 cal gas checks are 0.013" and the 50 cal gas checks are 0.023" thick. The 338 gas checks are so thin that they form a small lip that extends backwards from the base of the bullet. I think this is making them less accurate than bullet sized without the check.

I can not shoot the .339 bullets unsized in my 338 whisper as the bore is too tight.

Does anyone make a thicker gas check for the 338's? Thanks.

Ranb

if you think they are zinc.
try to cut them with a pair of wire cutters.
ww's will cut easily,zinc won't.
the only other maker of gas checks [i know of]is gator checks.

Alos, when you smelt them down, if you keep the temp below 700deg, the zinc wts float to the top & can be skimmed off.