I ordered some winchester brass for my 7mm WSM from Midway a while back.I ordered 4 bags(50 per bag),I got 2 bags in,and 2 were back ordered.I just got the 2 back ordered bags.They all appear to have the same lot #.There is a number on the bottom right hand corner of the bag E125312 B42.Is this the lot#?I just wanted to make sure before I mix them together.