All cold bore shoots always impact differently in ML and centerfire rifles. Keep the barrel wiped free of any lubricant before hunting and since we are talking ML just keep a running log of your cold bore shots and note the impact of each cold bore shoot and you can either sight the rifle to the correct point of impact you want, or aim a little low. Most of the time you only get one shot so I personally adjust the point of impact with my scope for a clean barrel cold bore shot. Beside cold bore and clean barrel there are other things that will effect bullet tragectory, such as temperature and humidity. Then again I wouldn't about those things. I would shoot my muzzle loader close to the hunting season to ensure the zero is correct and then just hunt and have fun.

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