Re: cold weather shooting
Did you sight it in at the same location (elevation) or at a different one ? It is always worth while to recheck zero prior to the hunt.
If your load data is from a substantially different temperature/elevation/relative humidity, you may want to verify the drop and not just the zero. Good data on ML bullets is rather hard to come by, so calculators are not much use until after you have all the field data down and then back calculate either MV, or BC to fit the measured drops in the known field conditions.
I have no idea of my MV for instance and if one chooses to believe the BC data on the bullet, well lets just say that could be a mistake. It is fairly well known that the BC's are overstated.