I would not leave the cap exposed to the elements anymore then I had to, but you will find that the hunterbolt is pretty weather resistant. Take a piece of handi wrap and put that over the breech to shed any rain or snow that might fall there. You can fire with that handi wrap in place. Actually you would probably be fine without the handi wrap. It is just another little extra. When you're on stand just lay your coat sleeve over that area. All you are trying to do is keep direct water out of there. But hunterbolts are a good rifle. You should be fine.