Ive had mine "sweat" both ways,,warm gun to cold air,and also cold gun to warm,,,keeping the gun,and powder,the same as outside temp is very important..cab of the truck works good for overnite,,,out of the weather but relatively same temp as outside generally is.I would still be leery to keep it in more than a few days at the most in perfect conditions.ive had 2 animals live in the past because of this mistake.powder and bullet are cheap compared to all the work,time,and money that goes into a hunt for that split second of opertunity?just sayin.co2 unloader at nite unloading doesn't foul the barrel like shooting it does.quiet too.