You're doing it wrong. Military kills aren't butchered. I'm not sure if there's a way to change that.
Get a dwarf and set his labor to hunting. Also, give him a crossbow weapon and some leather armor too.
EDIT: let me elaborate a bit more.
press [v] and go the the dwarf you want hunting, press [p]ref then [l]abor and turn on hunting, you may as well turn everything else off too. press [p]ref again then [ s ]oldiering and Hunting. Select the crossbow, leather armor, and a shield.
If you don't have a crossbow he'll wrestle the animals if you have a crossbow but no bolts he'll bludgeon them to death with the crossbow. The armor and shield is help alleviate the high casualty rate of hunters.
Anyway, he'll kill an animal and return the kill the the butcher's shop. Then the butcher shop will create a butcher animal job automatically (this can be disabled in the [ o ]rders menu, but don't do that). The butcher will butcher the animal. Then the tanner's shop will create a tan a hide job automatically (you have a tanner and a tanner's shop right?).
Make sure you have a refuse pile (I put mine outdoors) for the chunks, otherwise they'll cause miasma. You may want a different refuse pile for the bones and skulls (bones are used for bolts and crossbows). Also, a place for the fat. Otherwise, your butcher shop will get cluttered and the corpses will rot before anything gets done.
I hope that that's not too much information for you. Good job on using the wiki and telling us exactly what you're doing so it's easy to see what you're doing wrong.