I just worked up a good load for my 300wm using IMR7828,the problem is,I started with a 1lb. bottle and now I need to buy more.I want to buy a 8lb. jug so I will be set for a while.Should I expect a difference between the 2 different lot #'s of powder?If so,what should I do about it?I was thinking about using my chronograph to get the new powder to shoot the same as the old,by tweeking the load with the new powder.Is that the right thing to do?