I don't agree with the Weekly Stds. take on this, but they do note that the petition is to ban both lead shot and bullets. It is not just about big game rounds. I know some of the people at CBD and
AFAIK they are not anti-hunting at all (much less anti-gun). This is about pollution from lead.
Read thru the rule making file at the EPA site (big) rather than rely on characterizations by others. No question that it would alter ballistics.