All at once I have lots of centerfire ammo. I have had a bunch of 45 colt for nearly three years and now 44 special for a year and a bunch of 9mm this year. I am talking factory made and then I have a bunch of reloaded by a relative 38 special. It occurred to me that I read, on this forum I think, a year or two ago about keeping the boxes of 50 upright. It seems that the person writing said there is some risk in storing the boxes on their sides or upside down for some reason. I may be just confused...or maybe it was just some types of ammo. It seems like maybe it had something to do with lubricant becoming runny in heat and tainting the explosive...the powder. So, help me out here. I know ammo lasts and lasts but should centerfire be kept upright...meaning the way the tray boxes are packed....or ??????