A retired gunsmith friend gave me an old gun digest from the 1950s I think... Anyway, there was an article about Mr. Harvey and his zinc disc base bullets. A little flattering, but he did emphasize that pure lead bullets have alot less tendency to shatter than alloys. In his writings, Mr. Dave Corbin tells of failures with these zinc discs when they were undersize for the bore... [surprise! surprise!!] but if filling the bore and not over taxed, satisfactory... and his work led to the copper disk... he has several books on his web site free for the download. No pictures, but text discussing this product... good, free place to start... luck
