Play proceeds through a succession of ''hands'', each hand consisting of a ''deal'', ''the play'' and ''the show''. At any time during any of these stages, if a player reaches the target score (usually 121), play ends immediately with that player being the winner of the game. This can even happen during the deal, since the dealer scores if a Jack is cut as the starter.

Can we conclude that can you go out on a jack in cribbage?
yes