ball-bearing i thought it was a size comparision. there a b and bbb sized balls. BB guns shoot small BBS that are normally .177 caliber (4.5mm). a bb is a ball bearing that the gun shoots. the speeds...
I believe when I was younger My Grandpa said it stood for Ball Barrings....update: I always thought it stood for bullet ball.
It all depends on the model. Which one are you asking about? Their are over 50 different model BB guns
BB stands for "Bulletin Board"
While working as a disc jockey at an R&B radio station, he earned the nickname "Beale Street Blues Boy," which was later shortened to "B.B."