case volumes

It just isnt that hard to seperaate the brass and find the ones that have larger case volumes.

I size all the mixed rifle brass of one caliber at a time. I reprime all the cases. Next I seperate by headstamp and then weigh each headstamp. Then I go to my scale with the powder that I am going to use and weigh the charge that I am going to use. I transfer this charge from headspace to headspace noting the height in the case for each case stamp.

What I have found so far is that the heaviest cases have had the least volume. I then use this least volume to work up my loads.

Yes you can do the water method if you like making messes but a dry volume will work too.
 
Gotta say that, if the OP isn't a serious target shooter, weighing cases is hardly worth the trouble, as is filling cases with water. Way more important than that is an accurate rifle.

I used to spend a lot of time weight sorting cases and then prepping them to the nth degree. And I shot them in rifles with aftermarket barrels and tuned actions, and they did and do shoot great. Then I just got tired of all that prep work and started buying Lapua, Norma, and Nosler brass and using it un-prepped. And it shoots as good as all the brass I prepped.
 
Since SAAMI has specifications for just about all cartridges, my question is this: If I weigh my 30-06 cases, will those with the same weight have the same internal volume? That would mean I could sort my hunting brass by weight and not have to worry about different manufacturers.
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^^^^ what smoke and recoil said.

5K31MD, There are factors. I sort brass by head stamps. I am the fan of keeping cases together, most reloaders give up on keeping cases together when they tumble. I am not beyond tumbling 200, 300 or beyond cases at a time. Sorting after tumbling is no a problem because I use head stamps in groups of 20.

Then there are reloaders that repeat what they read and or heard over and over until it becomes fact? It is believed surplus cases are heavier than commercial cases, then it is believed the heavier case is caused by thicker brass. Not so; I have measured cases that were believed by most reloaders to be thicker because they were heavier. My surplus 30/06 cases have a case head thickness of .200”, my R-P 30/06 cases have a case head thickness of .260”. My surplus brass has a thinner case head than my commercial brass.

Then there is deductive reasoning; if the case is thinner but heavier the weight must be in the wall of the case body. Then we apply the ‘therefore’ explanation. Meaning if the case head is thinner and the case body is thicker the powder column in the surplus is longer and smaller in diameter than the powder column in the R-P case. Which is to say the powder column in my R-P brass is shorter and larger in diameter than the powder column in my surplus brass?.

Factors; does the long powder column that is smaller in diameter work better than the case with the short fat powder column?

F. Guffey
 
Exactly so. The head dimensions and the alloy can throw off a simple relationship. I once weighed a number of .308 cases and found there is a trend toward weight and capacity tracking, but the correlation was only good enough to get within 20% or so of actual measured difference in water capacity. It would get worse if the sample were bigger.

This article shows two lots of Winchester brand cases in .243 Winchester that both had the same 54.8 grains of average water capacity, but one lot weighed an average of 158.58 grains, and the other weighed an average of 166.44 grains. All that means is the brass was made in different plants at different times on different sets of tooling, perhaps by outsourcing in one or both cases (though I suspect the older, lighter, lot A was made at Olin's East Alton, Illinois plant and lot B might be an outsourced one. Finding a way to save brass material cost by minimizing the weight of the cases would obviously be in the manufacturer's interest. I'm sure they did it by making the heads to minimum dimensions.
 
F. Guffey, thanks for the information on case head thickness between surplus & commercial. I don't use surplus brass but if I did I would be looking for differences in volume & weight, I would of thought the case head thickness would all be the same do to the primer ignition. On surp!us is the flash hole larger to compensate for the thicker head.
 
On surp!us is the flash hole larger to compensate for the thicker head?
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No, I have a flash hole gage, I know of two other gages that belong to members of this forum. I have measured the diameter of the flash hole before and again after for the sole purpose of checking case head stretch.

Another member drills the flash hole in his cases to the same diameter; his rational? He said he wants all of his flash holes the same diameter just in case it matters.

F. Guffey
 
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