I used Mink Oil back in the early 80's when I first saw it and have just picked up another couple tins. It worked just fine for hunting, it's intended purpose. I've shot up to 20 rounds without having to clean and without loss of accuracy.
:For range shooting, I use spit & have for over 30years. both the mink oil and spit seem to hit the same POI, which is important. Other greases I've used, such as crisco blends, usually strike higher than spit lubed RB's, due to greater lubricity. Straight crisco didn't shoot well for me due to being too slippery, if there is such a thing. Also, the mink oil is suitable for cold weather shooting. The Crisco blends usually get to hard in sub zero weather and don't release from the ball. Accuracy is also poor at cold temps with crisco. The oil shoots just fine as does pure clear bear's oil, just as Ned Roberts said. Most people use too much heat when rendering bear's oil and get shortening instead. That's fine for making pie crusts or summer pathc lubing, but not for cold weather.