Because one is currently backing gun control and the other isn't
Are you referring to this NRA statement?
https://home.nra.org/joint-statement
I don't see this as backing gun control. If you know that Slide Fire asked BATFE if their stocks conformed to law and was approved and then say that BATFE should review and see if the stocks conform, do you believe that BATFE will say they don't conform to law? I thought it was a brilliant hoodwink. Believe what you want. They are not backing any new gun control laws.