Saskbucks, sorkrebel is bang on.

I have left my ML charged for up to 2 weeks, only if unfired and dry outside. If it is wet or fired clean it pronto. Is your ML stainless or blued? My experience has been that blued tend to pint or show signs quicker than SS. So if it is blued I would only leave it week in the dry unfired conditions. I always and mean always wipe down the exterior of the gun with rem oil after a day in the field. During off season I usually run some lube and dry patch it every few months and recoat with remoil on the exterior. My MLS is 5 years old and looks like new in and out.