x2tigrr. That is the best way to keep the powder consistent. There was a time, when I only shot a few rifles, that I would buy enough powder to wear the rifle out. That sort of went by the wayside, long before the rifle wore out as it was either sold or relegated to the safe. I still buy large lots of powder though. The powders are usually from the same lot but not always. I've found that if you get several lots in a batch, say a box of partial tins or from several tables at a gun show, that when they're blended, there is little if any difference from the last batch. This works for all powders, not just Varget and if you can afford to do it with all of the powders you use, you can usually get away with blending the new lots in with the old blend without changing anything. It is a really handy thing when you're shooting a bench rest rifle and you have a limited competitive barrel life.