The NRA likes being a power broker in the ebb and flow of politics in DC. IMO, they are focused as much on winning anything as they are on gun rights. I am not suggesting this is all bad, but it makes for some strange bedfellow situations now and then. it also means they agree to some things the rest of us are not overjoyed with.
They also focus exclusively on gun issues, which IMO is how they got sideswiped by McCain-Feingold. I think they thought it was so brazenly unconstitutional that there was no chance in hell any court would ever sustain it, plus it was not real gun legislation, so it was not in the forefront of their thinking at the time.
Ron Paul is not just focused on guns. He is interested in increasing personal liberty, and that means the size, scope, and power of government at all levels, and in all facets has to be trimmed.
That means sometimes he is not on the same side as the NRA.
Personally, I think he was wrong about the gun liability issue. Very clearly there is a strong element of interstate commerce there. OTOH, I am not a fan of this type of narrow legislation. If it is good for guns, why is it not good for every other legal product?