Weighing Cases to enhance accuracy?

OK, I can accept that, empirically. Although it would seem that cases of the same brand and from the same production run (lot) would exhibit very similar machined dimensions in the solid casehead.

I presumed that weighed cases graded for accuracy are always from the same lot of brass. My question assumes this. (Although I didn't make that clear)

I've graded a few sets of cases for volume variance using soapy water and found the method to be counter-productive.

Of course YMMV.

al
 
Alinwa

Al the last I heard Henry Childs bought 5,000 Lapua 243 cases and weighed them all to 0.01 grains.He kept them in bags of like weights and sold all of them but the largest like quantity.
I don't remember his exact numbers but it was alot of work for a limited number of cases.I trust he wasn't doing it to test his scales battery life so I keep my heavygun brass in individual groups of 10 with as little variance as I can achieve.

My loaded rounds have the same weight tolerance as my primers do.
Lynn
 
this post has alot of good points,except the part were some people think you should weight brass at all.this post should have been posted as "how to sort 1k brass into relay brass.this is how I sort my 1k brass.I start with a large amount of brass 300-500 peices.I do all the prep work first then weight them and put them into 25 peice lots.I the weights as close as I can get .1 to .3 will work.then I aneal them all then size them.this is important to get neck tension all the same.after that I load all 25 with good sorted bullets,bearing surfaces all checked,then shot them over a chrony.I pick my brass by speed .I pick the brass that speeds are the closest then throw out the highs and the lows.then I put the brass in order 2fastest will be first 2 siters.next 18 will be pu in order from slowest to fastest and shot that way .first 8 will be siters the next 10 record.this gets rid of all varyences.Bottom line is when picking brass for a relay out of 500 peices you can't just go eny miney moo.you have to have a process and weighting is only the first step.good luck and good shooting.:D:D
 
Henry Childs

Lynn said:
Al the last I heard Henry Childs bought 5,000 Lapua 243 cases and weighed them all to 0.01 grains.He kept them in bags of like weights and sold all of them but the largest like quantity.
I don't remember his exact numbers but it was alot of work for a limited number of cases.I trust he wasn't doing it to test his scales battery life so I keep my heavygun brass in individual groups of 10 with as little variance as I can achieve.

My loaded rounds have the same weight tolerance as my primers do.
Lynn
Click to expand...

Lynn:

I still have 300 + of that brass I purchased from Henry years ago. It was indeed sorted as you say. I also have, with his permission, a virgin reamer to the 6mm specs of the round he calls the 243 Williams (basically a 243 with a 6BR neck) which I obtained about the same time as the brass. I believe this batch of brass and reamer will cut a chamber in what I have reason to believe is the last barrel that Skip Otto ever fluted: 1.25 straight Broughton, 8T, 5C. I have been waiting to make this a special project. Maybe it is time.

Jim Hardy

Jim
 
Annealing

6.5fan, any chance of hearing your annealing procedure. My process is sorely lacking and I would like to learn more.

Maybe PM or a new post so we don't hijack this one.

Also, have you shot a series of cases again over the chrony. Has it retained the same velocity rankings?

Thanks,

Jerry
 
Jim Hardy

Jim Last time I e-mailed Henry he is still shooting his 243 Williams and loving it.
I offered him a free barrel and my reamer along with dies,bullets,primers,powder and brass to get him interested in a 6BR and he declined the offer.
I would build that rifle.
Lynn
 
In my opinion the weight tests must be done with brass from the same lot(1), with same number of firings(2), use bullets with same bearing surface (3), and with bullet weight same(4).
 
As lI stated above, I believe it to not matter,but I didn't realize the conflict it would cause here!!! I know different things work for different people. But the main accuracy still comes from more imortant things.I can say this,which i'm sure some of you will not beleive. Last year I shot new cases every match,only turning necks. I did not weight cases,sort them or anything. I won the 6 match agg at Hawks ridge,lost the ten match agg the last match because of wind conditions, and won light gun overall at the PA 1000 world open. Never once did I sort anything in brass,only trimming necks and blowing them out. I not saying that it does or does not make a differance, only passing on what worked for me!!!!
 
You don't wonder at all how well you might have done with matched brass?
You sound pretty content where you are.
 
I will give a three part opinion to sorting:

1st part -- there are Plus' and Minus' to sorting. On the Plus side: using sorted case will not hinder accuracy. I think it is very fair to say, one can research all they want, and you will not find anyone saying they hurt there accuracy by sorting.
On the Minus side: many obviously do not like the process and time it takes to sort.

2nd part -- it is my opinion, the larger the case capacity, the less important sorting is.
At the same time, the larger the caliber, I have the same opinion that it is not as important.

3rd part -- one sorts brass to equalize volume. So is weight even important? I find it is part of the over-all process, and that the volumes tend to fallow the weights, but not always.


A 6" drop funnel and H380 ball powder is my process. Dumping one to the next with a few trickles to top it off.
Cases need to be fire-formed, resized and trimmed equal (in my opinion).
I re-use the same powder over and over and keep it in a old jug. Only takes a few grains more then case capacity.
The pouring, trickling, and leveling I do in a large bowl.


Happy Shooting
Donovan Moran
 
Last edited:
Rem300ack

Which brass were you using?
If you use Lapua 6BR brass you can often times get 300-400 pieces within a grain.
If you use 300 Weatherby brass it can vary all over the place or be pretty consistent and is brand dependant.
Regardless you had a great year.
Lynn
 
The answer to your question Mike is I think(my opinion) is that there are more important factors than weight. I seat bullets with a presure gauge to determine neck tension,and use careful annealing. I think this is the most important. The main thing is there are a lot of good shooters out there that will take the glory on any givin day, thus what works for me may not for someone else. Bill shehanie told me one time to forget weighing cases and I kinda did.No matter what Bill has done alot of very good shootin in his life.....
 
Donavan,I agree 100 percent with you. I may, with a 30 cal. bullet and a big 300ack case be "cheating" the case sorting a little bit.I also agree that volume is what makes the powder charge consitant and not weight.Some will say that it is the same thing, but the same volume of powder is not always the same weight...
 
Rem300ack

Can you explain a little bit more about seating bullets with a pressure guage or perhaps post a picture of your setup?

Thanks, Joe
 
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