I've tried most of the above solutions and found them to be quite slow and still involve a lot of hand work afterwards... but Arm & Hammer Washing Soda (not Baking Soda), upon boiling, turns into a compound that will literally dissolve collagen. You can buy it at most grocery stores. Using this stuff, you don't have to pick the skin and/or cartilage off at all. There is of course a downside... It will also bleach the antlers if it splashes up on them. It's also capable of dissolving the connective tissues that hold the forward parts of the skull together, such that those will fall apart (though I suppose you could super glue them back together.