I loaded 15 cartridges today for .30-.30. It was once fired brass that I full length sized. I tested each cartridge in a Hornady cartridge gauge and they all fit easily. I then primed, loaded powder, pushed in bullets, and did the Lee factory crimp. I then tried each completed cartridge again in the Hornady Cartridge gauge and four did not fit this time. Well, I could push them in with moderate pressure if I wanted to, just not drop in like the others. Is this something to be concerned about? I will be firing these cartridges in a Marlin 336 lever action rifle.