Do you guys weight sort your Lapua brass, in 338 specifically. I've ordered 500 pieces of Lapua, but after sorting to 2 grain lots, I've got ranges from 325 all the way up to 335 grains. I've loaded within the 2 grain batches so far, but I would like to utilize all my brass. Am I likely to need different dope for these individual batches?
Is weight sorting Laupa brass necessarry?
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Necessary? No. But it can't hurt and it removes one variable when working up a load and shooting it for great accuracy.
If you think weighing something to precise numbers, do it with powder, I use a hi dollar scale, my ES/SD are single digits, and I don't weigh my brass primers bullets, spend less time on the bench and more time on the range.
Rather than sorting by case weight, consider sorting by case volume using a fine powder that settles well without having to use a Drop Tube or vibrating.
One local BR shooter uses H-414 and I use CFE223. Plug the flash hole with the tip of a golf tee you've whittled down to fit. Fill the case with powder while holding it over a bowl (I use a disposable paper one) and when filled strike off the powder level with the case mouth. Pour the powder on the pan of your scale and record the weight. Mark the case with the powder weight and repeat. Move you golf tee plug to the next case and repeat. Once you've measured and marked the cases you'll be able to sort into some logical groups of "matched cases" So you don't have to repeat the process just mark the cases with a fine pattern file or dremel took. I put "nicks" on the outer edge of the extractor ring much like one would mark hogs by "ear clipping". A series of "nicks" starting with a single one, then two, and three max. When I reach three nicks then I put three nicks on one side and start with one more 180 degrees apart. This allows me to have 7 groups of cases (those with up to 6 marks plus the ones with none) and I can re-separate them after I've run them in the tumbler.
Measuring by powder volume is far more precise than by case weight. If you take the time to measure and then mark the cases you only need to do it once.
If you want to make it "perfect", only measure once-fired cases for volume. This will eliminate any manufacturing variables although Lapua brass has less than most others.
That said, if you want precise ammo you'll go to the extra effort. If you want "good enough" then don't bother. Case prep (including volume measuring) takes time but it's tends to make the difference between the two. Maybe not enough to make a difference at 300 yards but a world of difference at 1k and beyond.
One local BR shooter uses H-414 and I use CFE223. Plug the flash hole with the tip of a golf tee you've whittled down to fit. Fill the case with powder while holding it over a bowl (I use a disposable paper one) and when filled strike off the powder level with the case mouth. Pour the powder on the pan of your scale and record the weight. Mark the case with the powder weight and repeat. Move you golf tee plug to the next case and repeat. Once you've measured and marked the cases you'll be able to sort into some logical groups of "matched cases" So you don't have to repeat the process just mark the cases with a fine pattern file or dremel took. I put "nicks" on the outer edge of the extractor ring much like one would mark hogs by "ear clipping". A series of "nicks" starting with a single one, then two, and three max. When I reach three nicks then I put three nicks on one side and start with one more 180 degrees apart. This allows me to have 7 groups of cases (those with up to 6 marks plus the ones with none) and I can re-separate them after I've run them in the tumbler.
Measuring by powder volume is far more precise than by case weight. If you take the time to measure and then mark the cases you only need to do it once.
If you want to make it "perfect", only measure once-fired cases for volume. This will eliminate any manufacturing variables although Lapua brass has less than most others.
That said, if you want precise ammo you'll go to the extra effort. If you want "good enough" then don't bother. Case prep (including volume measuring) takes time but it's tends to make the difference between the two. Maybe not enough to make a difference at 300 yards but a world of difference at 1k and beyond.
One theory is to figure out where the difference is, in weight and then decide the bulk of it is in the head area.
So, how do you measure the thickness of the head?
With a cut drill bit that just fits in the neck, turned to a point and inserted in the flash hole.
Now you measure from the case head to the end of the drill rod and establish a base line.
Measure every case and place them on a board, above and below the base line.
Write down the numbers. (sounds harder than it is)
You will establish a bell curve that will show you the thickness of the case head and this should/will be a lot more variation than the difference in wall thickness. And, it can give you an idea of
volume without filling every case with water or powder or potato chips. And, it is much quicker, once you dispense with the preparation details. I have been doing this for years based on a tip from a very accomplished bench rest shooter, who also does my barrels.
edit: I find it helpful to toss the five lowest and five highest, out of 100, for example.
Then I divide my cases into thirds.
Then I scratch a durable mark on the case head,
in a different location for each group
example: WW 308W
one group gets a mark like this "I"WW 308W
next is WW "I"308W
last is WW 308W"I"
The "i" being a scratch mark with a carbide scratch awl that is always visible, for sorting.
No need to handle them separately while tumbling, unless you feel like it?
you should chamfer the flash hole to make it easier to center the pointed drill rod!
* I use the culled cases for load development
So, how do you measure the thickness of the head?
With a cut drill bit that just fits in the neck, turned to a point and inserted in the flash hole.
Now you measure from the case head to the end of the drill rod and establish a base line.
Measure every case and place them on a board, above and below the base line.
Write down the numbers. (sounds harder than it is)
You will establish a bell curve that will show you the thickness of the case head and this should/will be a lot more variation than the difference in wall thickness. And, it can give you an idea of
volume without filling every case with water or powder or potato chips. And, it is much quicker, once you dispense with the preparation details. I have been doing this for years based on a tip from a very accomplished bench rest shooter, who also does my barrels.
edit: I find it helpful to toss the five lowest and five highest, out of 100, for example.
Then I divide my cases into thirds.
Then I scratch a durable mark on the case head,
in a different location for each group
example: WW 308W
one group gets a mark like this "I"WW 308W
next is WW "I"308W
last is WW 308W"I"
The "i" being a scratch mark with a carbide scratch awl that is always visible, for sorting.
No need to handle them separately while tumbling, unless you feel like it?
you should chamfer the flash hole to make it easier to center the pointed drill rod!
* I use the culled cases for load development
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Just a question out of curiosity. are all 500 pieces from the Sam lot number?
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Yes. It seems to me like a given weight of powder would liberate a specific and consistent volume of gas. Velocity would be more prone to variation from differences in bearing surface than case volume. Thanks all for the replies.
Weight sorting is always good! But imho if using a single quality maker its usually not a necessity unless you are doing some hardcore brass prep with it.
Well before uniforming the flash holes. Uniforming the pocket depth and checking axial runout on the necks is a perfect time to separate ones cases by water capacity. Now I would say you should trim to nominal length before doing capacity testing to keep the measurements valid. Of course weighing your projectiles is going to go without saying along with inside and outside neck turning
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This...i don't sort my nosler brass. Didn't stop my rifle from producing sub 1/2 MOA groups and i know i can't shoot the difference.
This ^.
Do it before you decap and resize. I'm with the others that it's probably not needed for mfg like Lapua. I don't bother. However, test some beetween various mfg's (Win, LC, Hornday, Lapua) load and chrono what you found, it will clearly illustrate how important case volume is.
I have to lean in favor of this ^^^ ...however, it may show more evident differences (imo) as you go up in case size (ex: RUM's & such) vs. a 308 or smaller capacity of that sort I haven't tested smaller casings*
BUT.. By weight-sorting (my/bigger capacity) brass I did see a shrink in my "es" as well as literally eliminated flyers triggered by significant velocity spreads. But my brass is not Lapua* I weighed +/-200 peices & had the lions-share of mine all with-in 3/5grains but some as high as 15 grains heavier! Everything I shoot while load developing goes through a chronograph, and there IS a difference in velocity in those heavy cases vs the average ones. So regarding the quoted reply-- case prep/consistencies start playing a role when you want repeatable groups case to case at any significant yardage. Definitely did in my situation.
It takes more time and is a pain in the ass, but I've seen a difference.. I intend to keep that in my own loading/prep routine, but to each his own
As stated above, case weight does not necessarily equate to case volume. However, a lot of high-level long range competition shooters swear by it. Although I think a lot of it is mental, I can understand that losing even 1 or 2 two points can change the outcome of a match among the top echelon shooters.
What really makes me laugh is to hear about someone weight sorting their brass to the nth degree, only to find out they are throwing their powder with a machine that is at best, accurate to +/- 0.2 gr or so. If you're not weighing powder to half a kernel accuracy, it's unlikely you will see much gain from weight sorting your brass. However, if you want to weight sort your brass, sort your bullets by weight, base to ogive, or by bearing surface, trim your meplats and point your bullets, or anything else aimed at extreme accuracy/precision, that's great if you can find the time to do it. All I would say is that you better know what your limiting source of reloading/shooting error is before spending all that time and effort. For many, I think it's far more likely the limiting source of error is an inaccurate scale, poor brass prep, even a rifle (or shooter) that won't hold small groups at 100 yd, let alone longer ranges. For these individuals, weight sorting brass or any of the other techniques will largely be wasted effort.
What really makes me laugh is to hear about someone weight sorting their brass to the nth degree, only to find out they are throwing their powder with a machine that is at best, accurate to +/- 0.2 gr or so. If you're not weighing powder to half a kernel accuracy, it's unlikely you will see much gain from weight sorting your brass. However, if you want to weight sort your brass, sort your bullets by weight, base to ogive, or by bearing surface, trim your meplats and point your bullets, or anything else aimed at extreme accuracy/precision, that's great if you can find the time to do it. All I would say is that you better know what your limiting source of reloading/shooting error is before spending all that time and effort. For many, I think it's far more likely the limiting source of error is an inaccurate scale, poor brass prep, even a rifle (or shooter) that won't hold small groups at 100 yd, let alone longer ranges. For these individuals, weight sorting brass or any of the other techniques will largely be wasted effort.
Short answer no long answer maybe given your consistency levels on other reloading operations
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What I find humerous is the number of people who say "Lapua brass is twice as expensive as Winchester". Winchester prices they use are often the price for a bag of 50 versus a box of 100 for the Lapua. Yeah, it's more but not 2X. For those who don't want to break in new brass very often, the life expectancy probably makes up the difference.
I will say that you can see a clear difference in brass when comparing flash holes. The nice round Lapua holes are more uniform than a lot of the irregular Winchester flass holes. You can also see a difference when annealing. The brass is definitely more uniform on the Lapua with fewer hot spots while in the flame.
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