RE: Wet Weather Tips
Most inline rifles are pretty weather resistant. Even the simple #11 percussion cap is very weather resistant. The new inline rifles are at the top of the wet weather ability to take moisture. The traditional rifles need a little more attention, but with the right things, will shed water as well as the best of them.
If your hunting with an inline the easy way is go to Wal Mart or any pharmacy and get some finger cots. These latex finger guards for cuts will slip over the end of the muzzle and basically seal it. There is no moisture that can get past them. Plus they do not have to be removed when you shoot. It will blow right through them. Their draw back.. get the extra large model, especially if you have a front sight on the rifle. Also be sure to take them off at the end of the day and wipe that part of the barrel off with an oil patch. The rifle will rust under them if you leave them on.
The breech area of the inline is basically water resistant. Notice I did not say water proof. Knight with the red primer holder claims to be water proof. I do not like that add. There is always something that can effect them. Some just more so then others. Still, if it is an inline with a 209 primer set up, you should be pretty safe. Not that I recommend you place that under a steady drip of rain water or pack it in snow, but keep your hand over that area where the rifle closes up to shed any water and when sitting, a small piece of plastic tarp laid across that area will also help shed moisture. But you should be fine. Open breech model rifles like the Black Diamond have a breech cover that will help shed water. You can also cut a chunk of garden hose and lay that over the entire open breech. The hammer striker will still slide under that when you fire, and normally blow that hose off the rifle.
Traditional rifles can pose the bigger problems but again, not all that bad. The finger cot or even a plastic baggie with a rubber band, can be put over the muzzle. That end is sealed at this point. If you're having a percussion cap, some simple ways to water resistant the rifle.. some candle wax around the #11 cap along the bottom after it is on the nipple will help. Also run that candle in a line along the stock at an angle. The water then running off the stock will hit the wax line and follow that away from the lock area a little. Another trick is take the valve stem cover off the tire of your wife's car. Cock the hammer back and put the valve stem cover over that cap and lower the hammer back down on it. This also acts as a second safety of sorts for you. The valve stem cover can be flicked off when you're ready to fire, or run a small piece of fishing line through the cap and tie it to the trigger card. Then when you throw it off, the cap will not be lost.
Flintlocks need special attention on wet days. Change out the pan powder often. Get a Cow Knee and put that over the lock to help keep it dry. Or a large baggie. Or keep the lock part tucked under your jacket when your standing around. If you suspect the powder might be damp, change it. Wipe the pan out with alcohol, make sure it is dry, and re prime. Also after you have closed the frizzen, take a candle and carefully wax the edge of the frizzen with the candle. That will help seal it. Then the main thing is to keep the frizzen dry (with a frizzen cover or cow knee) and the flint dry and sharp. I hunted last year in the snow and when the time did come, the rifle fired perfect. I was very pleased that all my little things I did to help the lock worked..
I am sure there are other much better ideas, but this is how I do it.