It won't work. Gun ownership doesn't make you part of a protected class. In other words, you'll have no legal standing to sue. If you want standing, their refusal must be based upon your membership in a legally protected class. That's why the central argument in these cases is always, "I'm not refusing to conduct business with these fags, I'm refusing to allow them to compel me to say things I don't want to say." If they were to try and argue they have the right to refuse service to fags they would lose instantly. Once the case is about compelled speech it's a whole different ballgame. The government cannot compel speech. There's no way around it. If the Supreme Court were to rule any other way the floodgates are open. Imagine if the government could require painters to include at least one transgendered person per every 5 persons depicted in any painting, or for book authors to include at least one gay character portrayed positively in each book. As bad as that is, then imagine that the government can require that government be portrayed positively in all artistic works. Compelled speech is a big deal.