I know that when I went through the NRA instructor course for the Boy Scouts, it was pounded in our heads that "weapons" were not permitted, but firearms, guns, and rifle was okay.
I try to stick with either of those and avoid the word weapon.
NRA Life Member
Big Sister: "Everyone in America is fine with the .30-30, except Mack. He has to shoot that .35 because that extra point zero fives inches will matter on Bigfoot."