New to reloading but not shooting. I reloading books to tech drawings of the 308 case says it measures 2.015", but the one reloading book say trim your cases down to 2.005. Then your Cartridge case gage does measure 2.015" on the high side and 2.005" on the low side. Are these the min. and max. length your cases can fall into and are safe to shoot. And what is the best case length to reload with. I have about 1000 cases to reload and just want to be clear what length to use before I start.