Did you ever hear the old term "not having enough sense to get in out of the rain"?
When flintlocks were in normal use you did not hunt in the rain.
You also did not fight battles in the rain.
You did not go out in the rin unless it was a dire emergency!
Phneumonia was one of the major killers of that time. If you got wet you might catch cold. If you caught cold you might develop phnumonia and die.
It just made good sense to stay home.
Percussion caps were better in the wet, and several batles of the CW were fought in the rain.
Cartridges virtually eliminated worries about wet charges so armies began fighting wars in the worst weather imaginable. More soldiers died of disease than of wounds, right up to WWII.
Now, we hunt when our employer tells us we can hunt. If it is raining on our day off, we hunt anyway, even with a gun that was never intended to be used under the conditions we expose it.
first the flintlock, not good in rain.
then the percussion, better but still moisture sensitive.
the closed ignition in-line should have been the next step, but wasn't. It was the technological missing link that never existed, making wet weather ML hunting possible?