It depends on the rifling of your barrel. If you have a 1:12" twist, stay with <= 50grain bullets. You can try up to a 55 grain but that's about it. Start your selection based upon that and what you are going to do with the bullet. If it is for target, then use a FMJ. If you want to shoot critters, use a ballistic tip bullet. Both will work for either use but they will perform better for their intended purpose.