Van
For any other application other than Benchrest, I would not hesitate to mix two different lots of the same powder. Such as, 683-03 N133, and 508-05-N133.
But for Competitive Benchrest. I like to get 96 pounds, (a complete hazmat), figure it out, and shoot it untill it runs out. When I am down to about 30 pounds, I order another 96 pounds pounds of what ever is available.
Just for your own information, a few years ago, Gene Bukys and I sat down with my Rail Gun and 7 different years of N133, all the way from 1994, to 2003. We chose a flat 30 grns for the load.
It was amazing that, when shot by weight, not volume, all 7 were amazingly close to the same velocity. Yes, we had to change the powder measure to achieve the same weight, some as much as .7 grns, which shows how consistant 133 is from year to year when you load it the correct way, by weight, NOT by volume. The density varied, but not the load and velocity by weight.
Incidentally, they all shot the same when loaded by weight as well.
the "Old Wives Tale" of some lots being "hotter" just did not show to be true when shot by weight......jackie