Bristol Palin -- Levi Johnston ... Quit Hunting and Pay Child Support!

Levi Johnston has his priorities screwed up ... he's buying cars, dropping serious cash on hunting and taking fancy trips, instead of forking over child support ... this according to legal docs filed by Bristol Palin.

In the new docs -- obtained by TMZ -- Bristol claims Levi isn't a suitable parent on many levels to get what he's after -- 50/50 custody. She says aside from the fact that he's $67K behind in child support, he doesn't even visit Tripp on a regular basis.

In fact, Bristol believes Levi is so deep in the red, it constitutes a felony under Alaskan law.

And this is the best part ... Bristol wants the judge to say out loud that Levi is voluntarily underemployed -- translation ... LOSER.