i tried weighing all of my cartridges once. i thought they would all weigh the same. but the sad truth is that unless you sort every single component and load the by weight, it won't work. it is good to be paranoid. do not ever loose that. it will keep you safe. as for double charging, the best thing you can do is look in every case (while they are still in the loading block, or other level surface) before you seat the bullet. use a flashlite. if there is a double charge, you will see it. it will be noticeable. as for your loaded rounds, in a quiet area, put each one close to your ear and shake it, if it sound different, AT ALL, i would suspect something was wrong. not very scientific, but without tearing them all down, it is probably about the only thing to do.