Rules published by the National Baseball Congress

Question
Our league rules are in accordance with National Baseball Congress for 13 year olds.  Our league states that the bat can only be a -8.5 or less, tonight a player on the other team used a -9 bat during his time up.  During his at bat there were runners on 2nd and 3rd base with 2 outs.  He proceeded to get a base hit to drive in the two runs.  We the coaches noticed the illegal bat and told the umpire who in turn called the batter out and nullified the 2 runs scored.  Was this correct and why or why not?

Answer
Denis,

I am not familiar with NBC rules, however, I can tell you that every level of baseball I've been associated with (NFHS, Little League, and this includes MLB rules too) have a stipulation that any illegal equipment that is found during the game is removed, but any action with such illegal equipment stands.

Please check with your associations playing rules for the correct ruling.

I hope this has helped.  Should you have any other questions, please don't hesitate to ask!

-Martin Hoover