weigh cases by internal volume or by total weight?

[gilmillan1]

hello,

I am trying to perfect my loads, and i want to start weighing cases.

I have heard of two methods. the first one, which is the simplest one, is to weigh the case as is. the other way is to weigh with water and then without water to get the total volume of the case.

can anyone who shoots at 1000 yards provide some guidance on this issue?

 

[gilmillan1]

if it is the more accurate way, i am willing to spend the time. i am really looking forward to winning a 1000 yard match, and the only way to do so is to perfect every single round.

 

[gilmillan1]

i have been in some matches wherein I have seen that everything is going well and suddenly that dreaded 9 show up. You made a right wind call, but the bullet dropped low or elsewhere. Every shot must be able to do what you need for it to do. Thats why i am taking extra steps in my reloading.

 

[Erik Cortina]

You can sort your brass by how it impacts on the target. Group all your X's together. Separate all your high 10's, low 10's, high 9's, and low 9's. The others just throw them away.

 

[tenring]

Hey Erik, (if they are Lapua), throw them my way.

Lapua is the only brass I ever buy, I have sorted by case volume, and found no difference in how they shoot out to 500 meters. I have concluded that Lapua brass is so good, that sorting by weight is a waste of time.

 

[gilmillan1]

Erik, so you propose to shoot 200 cases to find out where they hit, and then thereafter sort them in batches?

I mention 200 because that is how many rounds i have.

 

[jsthntn247]

You can sort your brass by how it impacts on the target. Group all your X's together. Separate all your high 10's, low 10's, high 9's, and low 9's. The others just throw them away.

Would you need to do this with at least 1x fired brass or would you be able to tell with new brass as well?

 

[Marksman63]

If you are going to spend your time sorting Lapua cases' volume for 1000 yds matches, it means you have also plenty of time for reloading and you are a top shooter and a top wind reader

 

[Joe Salt]

I've always weighed cases and had some pretty good luck, But I just started checking volume. Ive been using H-380 powder with a ten inch drop tube, with a plug in the primer pocket. You can get both from 21st Century. It takes a few tries to get the hang of it but if you have time, go for it. I haven't had a chance to test yet, shooting starts in two weeks. Oh I suggest you do it over a Clean small bucket so you don't have powder all over, and scrap the powder of the top of the neck with a razor blade. you will have to get the hang of how fast you poor the powder, that the learning part! 8)
P.S. I've also tried alcohol, and water. Too touchy one drop makes a big difference. Then you have to dry them out. ;D


Joe Salt

 

[Terry_M]

Thanks for the tip on using powder instead of water. I'm going to try that with some 760 and see how it works out. Would it be okay to just prime them then or should I still plug them to keep a few kernels from escaping into the primer itself?

 

[gilmillan1]

If powder works, I guess refined salt should work too right?

 

[Brians356]

Someone contemplating sorting by case volume might want to try an experiment to observe the relative repeatability of weighing water vs powder: Weigh the same case ten times, filling with water (to a mirror-flat meniscus) and H-380 (scraping away the excess powder using a razor blade) and see what variation you encounter with each method.

I've never compared the two methods in this way, but if I was as serious about 1000-yard competition as the OP, I'd sure want to know which was more repeatable for me (not for someone else.)

One possible advantage to using water is that it's something of a standard, and there are numerous published tables listing water capacities of cases from various manufacturers, for generalized comparisons.

For filling cases precisely with water, I suggest using one of these cheap disposable glue pipettes (also useful for actual gluing!):

http://www.stewmac.com/Luthier_Tools/Tools_by_Job/Gluing/Pipettes.html

 

[gilmillan1]

i think will try both methods. powder, water and salt

 

[Joe Salt]

Water has air bubbles Alcohol doesn't. But try them all like I did. :-\

Joe Salt

 

[gilmillan1]

Dmoran, have you tested to see the difference between cases with similar volume versus cases not subject to your volume test?

 

[gilmillan1]

thats what i want to improve: my vertical. I hate vertical problems at 1000, because I could be killing it and then those fliers show up!!!

 

[Erik Cortina]

I don't sort by volume and my gun shoots just fine, no flyers. I weight sort my brass and do my final sorting with hydro press. Bullets get sorted as well and powder charge weighed to the kernel.

 

[gilmillan1]

Erik, maybe its a combination of the weight of the brass and neck tension. I have a hydro bullet seater coming on the mail. Maybe that will do the trick

 

[Joe Salt]

gilmillan1 For vertical you may want to try seating depth and neck tension, but one at a time so you know what helped. Eric I remember guys at our club doing what you said. One would be in the pits and marking the shots as they came in, then sorted out the good ones. Donovan seems to think volume, so I just may do the sorting along with the checking volume! Do them both can't hurt.

Joe Salt

 

[wolley]

Check the volume on cases only fired in the chamber you will be competing with.
Before resizing. Leave the fired primer in place.