Posted this on the Reloading Forum as well....

What do you competitive long range shooters do when you run out of the powder used to develop the accurate load you have for your rifle?

The next 8#'er you get may not be of the same lot.

Do you run through load development all over again, except you already have a good idea?

Example: 75 gr is my load with a 168gr A-Max. Will it differ much with the new lot of powder?

Some brands of powders are very close from lot to lot. I usually compare chrono results and get in the same velocity range. I then check my tune.
Usually works with VV powders.
Butch

Thanks Butch.

I'm shooting W-780 Supreme. Any experience with it?

You know, I do have some, but have never used any.
Butch

Thanks for the input Gentlemen. I think my questions have been answered!

You know, my post looked like w powder. I was actually saying V V or VihtaVouri Oy.
Butch

Pound to pound in containers I've found variations in volume/weight ratios for powders. The old stuff gets dehydrated and the new stuff in the same volume weighs more.

If you load by weighed charges on a scale, the newer power will be less volume for the same weight.

In either instance, you're not getting the same charge.