I also want them to be single issue. It's okay for them to take a side trip to contest McCain-Feingold when it interferes with their Second Amendment efforts.
We have, what, 4,000,000 members ? Let's say they also adopt, um, environmentalism as one of their principles. If half of the members disagree with that, the NRA now has only 2,000,000 members. Then they adopt anti-abortion, for instance. Half of the members disagree with that: they're down to 1,000,000 members. Then they add immigration amnesty. Half of the members disagree with that: they're down to 500,000 members. And so on.
To remain the greatest force for RKBA that the world has ever known, it is important to stay single issue.