Weight-Sorting Cases: Is it Worthwhile?

If you really want to be obsessive; why not weight sort your already weight sorted cases in order of lightest to heaviest, organize them like that in the box and shoot them in that order? That way you'll have the smallest possible difference in weight in every group or string you shoot; a group of 5 would have 10th the variation as a box of 50. I was shown that one by a guy who ran all his cases through a lathe to square the face of the caseheads and match rim thicknesses before he would even think about sorting his cases in order of weight.

Why stop there? After weighing all your primers to 1,000,000th of a grain why not load them in order? Primer compound is about 1000 times more powerful than gunpowder.

I'm too busy sorting my socks into lucky and unlucky piles. Gives me confidence. ;)

If you start with a large enough batch of brass you can find hundreds that are within a tenth of a grain. If you have an even larger batch of brass you can sort into lots that are within 1/2 of a tenth of a grain.

Then you don't need to weight sort within your box.
 
Words you will never hear from a top F Class shooter...
"F#*K it, that's good enough."

Reloading is also full of a lot of myth and lore, including (probably even more so) at the highest levels of competition.

I am very open to seeing any extensive studies/tests done that isolates all variables except variances in brass weight, that conclude that sort weighting brass does have an observable and measurable effect on precision.

To date, there is none. Its all anecdotal tales that comes from very uncompelling and unscientific data sets.

If high quality data exists that suggests that weight sorting brass has any measurable effect on precision, I'm all ears (as I'm sure many others are as well). I personally don't spend more time performing more steps just in the hopes that it may help.
 
If you start with a large enough batch of brass you can find hundreds that are within a tenth of a grain. If you have an even larger batch of brass you can sort into lots that are within 1/2 of a tenth of a grain.

Then you don't need to weight sort within your box.

Or you can cut that to a fifth on a ten shot string. Unless you're saying F-it that's good enough?

I shoot F- Class too; they let anyone do it. ;)
 
Reloading is also full of a lot of myth and lore, including (probably even more so) at the highest levels of competition.

I am very open to seeing any extensive studies/tests done that isolates all variables except variances in brass weight, that conclude that sort weighting brass does have an observable and measurable effect on precision.

To date, there is none. Its all anecdotal tales that comes from very uncompelling and unscientific data sets.

If high quality data exists that suggests that weight sorting brass has any measurable effect on precision, I'm all ears (as I'm sure many others are as well). I personally don't spend more time performing more steps just in the hopes that it may help.

Couldn't agree more. But if you feel it works for you, fill your boots. I am more concerned about reading wind better than the difference in the weight of a piece of brass. I don't shoot F Class but someone I have shot with and is one of the best F Class shooters in the country doesn't sort brass by weight and he seems to do pretty good without doing it.
 
It might be worth providing a little context to the whole weight sorting thing...

Lots of guys out there use scales that are not as accurate as they think they are. If you happen to be one of those guys, it might be that weight sorting cases will not matter as much as it would for a guy who uses a more accurate scale.

Another point on this is in the establishment of the root causes of velocity variation. I have posted many times that the angular offset of the bullet as it enters the rifling is related to the velocity spread. Therefore a long tight freebore diameter will provide the best chance of ensuring the bullet enters the rifling straight. Add that to tight neck clearances and the chamber is set up for low SDs. If you dont have your rifle chambered like this, then you are likely to get so much velocity spread as a result of sloppy throat and neck, that it may negate the brass sorting benefit.

So to this point the benefit of any efforts to improve are relative to all other efforts that may have been made. If you have never considered the other possible root causes of velocity spread and made efforts to address them as well, then weighing brass for you may be of little benefit.

So, if you cant get behind weight sorting brass, you probably cant get behind a proper analytical balance that is truly accurate enough and you sure as heck never did a chamber cast to evaluate your throat... etc etc,, So for that guy there is no point to anything that requires additional effort, money or thought.

If you are on a quest to do the best you can, then do whatever you think is the next most important thing and don't listen to anyone who says it makes no difference. They will never understand how it does.
 
I personally wouldn't bother weight sorting Lapua brass from the same lot. It always seems pretty consistent.

Maybe you should bother. Just because it's Lapua doesn't mean you shouldn't weigh it. I have seen enough inconsistencies in Lapua brass to question the price being charged for what is supposed to be premium brass. I have had to clean out flash holes from just as many Lapua as anything else and had to scrap several pieces where the necks were deformed. If you are looking for consistent accuracy you should sort. It does make a difference.
 
It might be worth providing a little context to the whole weight sorting thing...

Lots of guys out there use scales that are not as accurate as they think they are. If you happen to be one of those guys, it might be that weight sorting cases will not matter as much as it would for a guy who uses a more accurate scale.

Another point on this is in the establishment of the root causes of velocity variation. I have posted many times that the angular offset of the bullet as it enters the rifling is related to the velocity spread. Therefore a long tight freebore diameter will provide the best chance of ensuring the bullet enters the rifling straight. Add that to tight neck clearances and the chamber is set up for low SDs. If you dont have your rifle chambered like this, then you are likely to get so much velocity spread as a result of sloppy throat and neck, that it may negate the brass sorting benefit.

So to this point the benefit of any efforts to improve are relative to all other efforts that may have been made. If you have never considered the other possible root causes of velocity spread and made efforts to address them as well, then weighing brass for you may be of little benefit.

So, if you cant get behind weight sorting brass, you probably cant get behind a proper analytical balance that is truly accurate enough and you sure as heck never did a chamber cast to evaluate your throat... etc etc,, So for that guy there is no point to anything that requires additional effort, money or thought.

If you are on a quest to do the best you can, then do whatever you think is the next most important thing and don't listen to anyone who says it makes no difference. They will never understand how it does.

And yet lots of matches have been won and world records have been set with basic powder throwers and scales.

At some point, we are working against the weakest component. I highly doubt that our scales are that component (in most cases).
 
How about primer weight-sorting?

I am a fan of primer weight sorting but only of you have an analytical balance ... not a milligram balance.

The weight variation of some primers can be inside the accuracy capability of a milligram balance, so if you are not using an analytical balance, you are sorting according to scale error and not primer weight.

My analytical balance weighs to 0.002 grains (plus or minus less than 0.004 grains) and that makes primer sorting worthwhile. A milligram balance weighs to 0.02 grains plus or minus 0.04 grains, for a total accuracy error of up to 0.08 grains.

To put that into perspective, I've weight Federal gold medal match primers that are all within 0.08 grains. I've also weighed Winchester primers that varied by 0.2 grains.
 
And yet lots of matches have been won and world records have been set with basic powder throwers and scales.

You are correct... 20 years ago for long range. Back in those days I won almost every f class match I was in with a Dillon 0.1 grain scale.

Even recently at short range you are correct only because velocity spread at short range does not mean much on 100 yard group sizes. Just the same I would hardly call it an advantage to use a powder thrower at any distance. Sometimes people win in spite of their mistakes, not because of them.

We can't exactly rule out good old fashioned dumb luck either. I've been in matches where the relay a shooter was on just happened to coincide with light predictable winds, and for no good reason the other relay got hit with switchy winds. If the best shooter is on the tricky relay and the second best is on the easy relay, the second best shooter will likely win.

I've seen international matches where the home country team is positioned on the light wind side of the range and the foreign guys are on the windy side. Lots of ways to manipulate match results if you're the organizer.

I can recall an F Class match where the rifles and ammo were supplied, and guess who was the first to shoot that relay... The God Squad Jerry Jerry Miculek and associates. By the time we got to that stage they were spraying down the barrels to cool them off.
 
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You are correct... 20 years ago for long range. Back in those days I won almost every f class match I was in with a Dillon 0.1 grain scale.

Even recently at short range you are correct only because velocity spread at short range does not mean much on 100 yard group sizes. Just the same I would hardly call it an advantage to use a powder thrower at any distance. Sometimes people win in spite of their mistakes, not because of them.

I'll agree that better equipment will only has the potential to help, not hurt.

But at some point you are really fighting against the law of diminishing returns.

For myself, SD's of ~3-5 are very easy to obtain with my equipment, components and process. If someone wants an SD of 1-2 (and I'm talking 30+ shots, not just over 3 or 5 shots), then something needs to change. I have not achieved SD's of 1-2 fps (again talking big sample sizes, 30+), so I'm not the person to talk to. Obviously something needs to change in my equipment, components and/or process.

People need to find out what level of performance they are happy with, rather than chase ghosts. For me, I'm very happy with consistent SD's of ~3-5 fps. Perhaps for others that number is lower, and good for them if they can sustain that.
 
I'll agree that better equipment will only has the potential to help, not hurt.

But at some point you are really fighting against the law of diminishing returns.

For myself, SD's of ~3-5 are very easy to obtain with my equipment, components and process. If someone wants an SD of 1-2 (and I'm talking 30+ shots, not just over 3 or 5 shots), then something needs to change. I have not achieved SD's of 1-2 fps (again talking big sample sizes, 30+), so I'm not the person to talk to. Obviously something needs to change in my equipment, components and/or process.

People need to find out what level of performance they are happy with, rather than chase ghosts. For me, I'm very happy with consistent SD's of ~3-5 fps. Perhaps for others that number is lower, and good for them if they can sustain that.

I agree KT, but to get spreads as low as you are getting takes more than any one thing. As I've said above, you need a stellar chamber spec and a good pipe fitter that does not cut your throat over size. After that, everything matters, its just to what degree we are willing to chase it.
 
I agree KT, but to get spreads as low as you are getting takes more than any one thing. As I've said above, you need a stellar chamber spec and a good pipe fitter that does not cut your throat over size. After that, everything matters, its just to what degree we are willing to chase it.

I will agree that chamber specs, and the person cutting the chamber (and their knowledge and skillset), is a very important role in the equation.
 
What is an "analytical" balance? A digital scale?

Not sure where that phrase comes from - in another life, I was involved in a corporate air quality study - required dust to be weighed on air sampling pump filters - had to be repeatable and "correct". Scale used was in the site's Metallurgical lab - a Mettler brand - had to first send it off and get it calibrated to an NIST standard - so like 4 or 5 decimal places (maybe 6?) after the "0" - in grams. And we sent in multiple "blanks" to be weighed along with real samples - so Lab people would weigh a new filter, assemble a cartridge - give it a number. We would run air test or not, and send cartridges back to them - some had air samples or some had not been used - they had to dismantle the cartridges and weigh the filters - tell us how much dust, in tiny parts of a gram, that we had collected. Mucho lawyer types over-looking entire process - do not think "mistakes" were being "allowed". That scale was a balance beam - not a digital readout - I have no clue if that was an "analytical" scale or not.

Similar, but not identical, process for setting up the air sampling pumps - what was the true air volume that they were drawing through the filter over time - was not as "exact" as was the weight from the filters, for some reason. I seem to recall all that we did had to match up to a NCGIH or some other alphabet USA standard for air quality measuring.

Led me to believe is nothing magic or "accurate" about digital readouts - I have at least two callipers from NAPA - says right on their box they are "accurate" to .001" - but their digital display shows 4 numbers after the decimal point. Might use one and fool self into believing that you are measuring to the 10-thousandth, but that is not what that device is capable of - the maker said so - sort of "lucky" if the third digit is correct - I suspect the fourth number is pure fantasy. I also have a Mitutoyo micrometer that says it is accurate to .0001" - and, as per "experts", periodically need to use the "standard" that came with it - as per instructions - to have reason to believe that the four numbers after the decimal that you get are "real" values, that someone else could also get, with their calibrated measuring device.
 
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I am a fan of primer weight sorting but only of you have an analytical balance ... not a milligram balance.

The weight variation of some primers can be inside the accuracy capability of a milligram balance, so if you are not using an analytical balance, you are sorting according to scale error and not primer weight.

My analytical balance weighs to 0.002 grains (plus or minus less than 0.004 grains) and that makes primer sorting worthwhile. A milligram balance weighs to 0.02 grains plus or minus 0.04 grains, for a total accuracy error of up to 0.08 grains.

To put that into perspective, I've weight Federal gold medal match primers that are all within 0.08 grains. I've also weighed Winchester primers that varied by 0.2 grains.


Maple, what are the results of group size when you sort the primers? Are group sizes the same but poi is different?
 
What is an "analytical" balance? A digital scale?

Scales are basically sold according to the metric system with a coversion to other units of measurement.

So they come in different levels of "readability" 0.1, 0.01, 0.001, 0.0001, or they may confuse things by specking it out as 0.1mg, 0.001 mg etc

So a milligram balance will read in grains increments of 0.02 grains, An analytical balance will read in increments of 0.002 grains.

Accuracy is usually but not always about plus or minus twice the readability. So a miligram scale that reads in 0.02 grains is accurate to 0.08 grains. an analytical balance will read 0.002 grains is generally accurate to 0.008 grains.

Obviously cost will affect this. You can get $40 scales on Amazon that displays to 0.02 grains but they are fake posers. I'm really talking about the better scales that will generally cost upwards of $600 for a milligram balance and upwards of $1000 for an analytical balance.

Basically an analytical balance is ten times more accurate than a milligram balance. For primers you truly need analytical balance accuracy.
 
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