re: CNN on AR-15s

I took the family to DC this past Oct. for fall break. While at the Smithsonian Air and Space they had a display of ammo that different planes shoot and other weapons.

While my son and I were standing there looking at this guy and his adult son came up and were talking about which of those fit in an AR.

I don't remember exactly which one that they said it was but I pretty certain it was the 30mm that's used in the A-10.

My 11 year old heard them and just started laughing which made me laugh. I was almost embarrassed when my son said in a rather loud voice "what an idiot!" I kinda lost it after that...