I agree with the notion of abolishing the GFSZ law, but signing a petition is, IMNSHO, not the way to go about making that happen.
An email to your three Congresscritters, followed up by phone calls to both their local district office and their DC ofice, stands a much better chance of actually getting their attention. Identifying pro-RKBA members of both houses, even if they do not directly represent your District/State, and communicating your support for a bill to repeal the GFSZ law beats signing a petition.
Quite frankly, IMNSHO, these petitions are just another means of placating the populace into believing they have "done something." It takes work to make something like this happen. For some an email and a phone call a week really is hard work - but my limited experience is that folks think it is hard work because they think they do not know what to say or how to say it. The truth is that almost none of the correspondence/phone calls ever reach the Representative/Senator directly. But that's OK, because some legislative aide is feeding them a daily/weekly/monthly tally of the number of contacts for and against juist about every issue under the sun. Also, if you become a frequent correspondent/caller you may be able to develop a personal relationship with the legislative aide- which means your contacts carry just a little bit more weight than a contact from a one-time writer/caller.
Again, I fully support the repeal of the GFSZ law, but just cannot get behind the notion that a petition will have any impact.