I've shot my gun after a year with it in there and went off no problem hit bulls eye. Wouldn't recommend keeping it in there for a year but 2-3 weeks is perfectly fine. I forgot to unload after the season one year that is how it happened to me.
My dad told me a story about when his uncle first moved into his house. He bought the house from an older guy from what I remember. He found an old rifle in the basement with a bullet and a charge of black powder in the barrel. IIRC, the guy told him he had left the gun down there years ago and had no idea it was loaded. My dad's uncle, thinking the powder was no good, removed the bullet and threw the powder in the coal stove. I'm pretty sure it blew the stove pipe off. He kept the gun afaik and shot it. So as long as the powder is dry would be my guess. Dangerous though...
As long as the rifle is kept in a dry enviroment, i wouls say the powder would ignite for sometime. I too have seen rifles left loaded in a guncabinet for a year and still go off.
My friends dad would load his inline the first day of season, he would use a peice of wasp or hornet nest between the bullet and powder and if he didnt shoot it all season he would stick it in the cabinet till next year with no problems. He said the bees nest would keep the powder fresh, not sure if this is true, i always wondered about it, has anyone ever heard of this before?
Pellets in the barrel no different that stored elsewhere. Unless patch is a bit moist/greasy and fouls the powder.
But I would suggest You hang a tag on it saying it is loaded.
<span style="text-decoration: underline">Example why</span>
Guy has a loaded ML in his garage (so as not to warm up and sweat). Before going out to hunt "the next time" something unexpected happens. Someone else picks the gun up, no tag, Guy not around...
I was out the last day of 2B doe season last January.I got home that evening and we had company at the house,so I just gave the gun a quick wipedown and threw it in the gun safe.Forgot all about it until I took it out in early ML season in Oct.Put a cap on it and shot a doe,no problem.It was 100gr of White Hot pellets and a Powerbelt bullet.Everything is pretty much airtight in there,and unless it was a damp and rainy day the last time out,there is really nothing to worry about.I wouldn't recommend it though.