Here is my mom's secrets for all gamey meats...remove all visible solid fats and silver skin (most of you know that).
Make sure that you remove all blood from bruised meat when processing. Cut or scrape what you can off.
In a vessel (bowl, large pot, basin etc.) large enough that the meat can be completely submerged and not touching the sides, place the meat in the center. Cover completely with cold water and let sit a few minutes and drain. Repeat this until water is clear or only barely pink (is a small piece like a rabbit you can rinse under running water).
Cover the meat again with cold water and add at least 1/4 cup white distilled vinegar for each quart based on the size of the container (you can use red wine vinergar also but it will make the water a bit pink) and refrigerate 12 hours. If a large piece of meat consider splitting into 2 pieces or replace vinegar and water solution and soak refrigerated 12 more hours.
Pat the meat dry and let air dry well if you are going to freeze. Make sure to get all the air out of your freezer package to maintain freshness. Done properly I've eaten rabbits 6 months later that were just fine.