GMTA! This is exactly the tack I took when debating the point with liberals at work and the leftmedia during the counter-MMM rallies. Twice when I used it, the reporter/reporterette was black, and it had a telling effect. I'd follow up with "Color me black -- my rifles already are".
I actually had one say (off camera), "I think I see your point..."
This should be on every gun owners truck/car as a bumper sticker.