When weight sorting the 308 family of cases what is an acceptable weight range? 1 grain and under, 1.5 grain and under? These are not for formal targets, just doing an experiment. They will be used for informal target practice and maybe later for hunting.

Steve E..........

Well, if it's your experement, you decide.
You could start sorting them and you may end up with enough within a tenth of a grain and then try to out shoot them with a control mixture of ones about 3to 4 gr difference.
John L.

Start with 100 Win. 243win brass. uniform flash hole in and out. Weight cases, put in rows by 1/10 gr. wt. difference. When all cases are weighed i try to makes lots of 20 or more close to the same weight. Here is what some of the last batch of Win. cases looked like. (High 170.9 gr. to Low 166.5 gr all cases.) Lot 1=170.9 to170.5 7cases. Lot 2=170.4 to 170.0 18 cases, 169.9 to 169.5 2 cases.LOT 3 169.4 to 169.0 16 cases. Lot 4=169.9 to 169.5 25 cases. LOT 5= 168.9 to 168.5 11 cases. The rest of the cases are in use and only go by their lot number now, so no weights on them. To make up 20 rounds i use the next higher or lower lot. 100 rem cases were 161.0 gr. to 166.6grs. To conduct a test to see if weighing cases made a difference here is what i did. I took 5 of the very heavest and 5 of the lightest, fireformed, turned necks, shot 5heavy for group, 5lite for group. Then to compare i shot groups with 3heavy&2lite. Then a group with 3lite&2heavy.Same 10 brass. The best groups were with the brass weighing closer to each other. A small test, but proof to me that weighing brass works. Not worth the trouble unless your have a very accurate rifle.

243
Thanks for the info, that is kinda what I'm doing. Looks like you are using about .5 grain for your range on the high and low for each group of brass. I opened a 50 count bag of Winchester 7-08 brass and found brass from 156.2 all the way up to 160.9. That seems like a lot of variation. Hhhhmmm wonder what about Remington????

Steve E.........

When I'm really trying to get the best accuracy from an field weight rifle I use brass that is +/- 1% from the median (average). If I'm only concerned with hunting loads then I'll go with +/- 2%.

Woody

That's too big of a word for me Woody.

Steve E.......

Think of weight sorting like this.
Brass density is about 8 times the density of powder.
Decide what the maximum powder charge variation is that you will tolerate.
The equivalent space in brass volume would be 8X larger in weight.
If you will live with ± .2 grains of powder then the case could vary by ± 1.6 grains for the same volume variation.

Not scientific but it puts things into for perspective for me.

Steve E.
I've found that Winchester brass in .308 is more uniform than Remington or Winchester in 7-08. I buy Winchester brass in lots of 100 for my 7-08AI and neck it down a little at a time until I get a good crush fit and load them up. I don't sort by weight until they have been fireformed in my chamber, tumbled, sized, all cases trimmed to the same length as the shortest cases, and the primer pockets have been uniformed and flash holes reamed. Then I weigh and sort into twenty case groups. Actually, that's not always possible. Some cases have pinched necks right out of the bag, or are so far off from the specs of the other cases that I just use them for dummy rounds.

In my experience you'll probably need a rifle capable of 1/4 MOA to notice much difference in accuracy . I had all my Winchester .243 brass sorted but after some experiments I have it all mixed up again . The rifle will shoot down to low 3's for 5 shots with mixed brass .
I found Lapua brass to be so consistent that it would be a waste of time to sort them if you weren't right into benchrest .