weight sorting rifle brass

[dodpilot]

Question: Through personal experience, have any handloaders found evidence to the contrary?

“[I]n practical terms there is absolutely no reason to weight-sort cases as a precision-improving step. These tests include cartridge cases of the same brand that have been prepared identically, but with weights varying by up to 10 percent. That’s an absolutely huge variance that should eliminate the possibility of loading ammunition that will deliver a high level of precision and an extremely low level of velocity deviation according to conventional wisdom. Many handloaders sort brass into groups according to less than 1% [one percent] weight variation.” -- Kyle Lynch. “Raise Your Modern Precision Rifle Skills.” The Complete Book of Reloading, 2017. pp. 72-73.

NOTE: In compliance with this site’s “Copyrighted Material Policy” located under “Forum Rules”, the above article extract is four (4) sentences in length. To “44 AMP” and other staff members, there is no URL for this extract. It is taken from hard copy publication.

[Metal god]

A 10% swing is huge , 308 cases weigh anywhere from 160 to 190 grains but I rarely see the same head stamp have more then a 3 or 4 grain swing . 10% would be 16 to 19 grains . That's just not going to happen . So does the quote mean a 10% swing from brand to brand . If so then yes that could happen no problem . It's one of the very reasons we say separate your brass by head stamp .

Here are some 308 case numbers in grains ( averages & extreme spreads ) I just ran in the last few months . They are all 10ct samples of 200+ ct lots

Brand ------weight------ES--------H2o--------H2o/ES
LC-09------185.4-------1.7--------54.9--------.4
LC-10------184.5-------2.9--------54.8--------.6
LC-LR------184.3-------1.4--------54.97-------.8
LC-14------183.5-------2.2--------55.1--------1.2
Lapua------179.5-------2.1--------55.6-------.6

You all can evaluate those numbers and see what's there but as the numbers would seem to indicate . The LC-14 cases should be the worst shooting of the bunch and they are in fact the least consistent shooting lot of the bunch .

I find it interesting that the LC-10 and Lapua cases had the highest case weight ES and yet had the lowest case volume ES .

I'm also considering combining the LC-10 & 09 lots together seeing how they are virtually identical as far as case volume numbers go . What say you guys ?

[std7mag]

If your shooting like MetalGod, and some of these others on here, then sure, sort them out by weight.

If your just a "casual" shooter(range once a month, and hunting) then it's not worth the effort...

[dodpilot]

Metal God,

Did you mean that LC-Long Range has an internal water capacity of "54.97"?

[Metal god]

Yes , corrected thanks

[firewrench044]

I weight sort rifle cases, mostly for competition
but also for hunting
223, 308, 3006, 8mm Mauser, 303 and 7.62X54R

Its my understanding volume sorting is better
but I have been doing fine with weight sorting

I sort both cases and bullets

When I started I found it reduced group size in
223 by at least 15% and as much as 20% in
3006 and 8mm Mauser ( same head stamp and year )
It eliminated that -CENSORED--CENSORED--CENSORED- flier completely
Now when I get a flier I know I did it and can usually
call where it will hit

I shoot at 200, 300, and 600 yards
Any time you can reduce group size 10% or more
it will make a big difference in scores

Hunting -- most of my shots in S. Florida are 100 to 150 yards
( heavy cover, longest shots are in citrus groves )
so at that range the big difference is no fliers and I know
its going to hint where I aimed, as long as I do my part

[dodpilot]

Firewrench044,

What do you mean by "volume sorting"?

[Metal god]

Case volume is much better then just case weight .

[jwrowland77]

Sorting by weight is useless....sort by case volume if you want consistency.


Sent from my iPhone using Tapatalk

[firewrench044]

dodpilot --
Volume sorting is, filling a case with a liquid and sorting
cases by that amount of liquid
( that liquid is measured by weight or volume )
( the type of liquid varies )

Sorting by weight does work
It may not be as precise as volume sorting
but it suits my purposes, its fast and easy

Metal GOD --
you are correct volume sorting is better
but not that much better

jwrowland77 --
you are wrong !!
it may not be as precise but it does work

I shoot at 600 yards not 1000 plus
iron sights not a scope
223, 308 and 3006, sorting 2000 to 4000 cases in each caliber
( i also sort hunting cases 308, 3006 and 8mm Mauser )
no matter how you do it is time consuming

[Unclenick]

Yes. I once sorted a bunch of .308 cases by weight, then measured their case water overflow capacity. There was a negative correlation (negative because as weight become greater, volume gets smaller), but it wasn't tight. Weight difference, divided by the specific gravity of brass, predicted volume difference with about ±20% accuracy. Not great, but not useless, either. This happens because the extra weight can be due not only to a wall thickness or head thickness variation. It can also be due to a wider head or shallower extractor groove forward relief angle, or a different extractor groove width or different rim thickness or chamfer angle, all of which have tolerances, but none of which affects internal volume.

[T. O'Heir]

It won't make a lick of difference unless you're bench rest shooting. Even in long range target shooting, where the bull is 24" diameter, you won't notice any difference.

[Unclenick]

I won't go quite that far. It depends on the chambering. With .300 Win Mag, for example, the brands of brass with the least capacity are Tula and Remington at around 88 grains case water overflow capacity (varies by lot, of course), while the most generous case, Norma, has almost 96 grains of case water overflow capacity. That's enough difference that putting a maximum Norma case load into a Tula or Remington case could add close to 25% to pressure, depending on the powder. Maybe not quite into the US proof load range, but at the bottom end of CIP's proof pressure. It's enough that QuickLOAD has separate listings for several makers of .300 WM brass as if they were different cartridges.

.308 Win probably comes in second for variation, with some makes of cases as heavy as 190 grains (these are 7.62 NATO cases out of South Africa, IIRC), and some as light as 150 grains (Winchester 1992 Palma brass, for example) and the range of capacity reflects that weight fairly accurately, being in the 55 to 59 grain range. It's enough that a max load developed for the Winchester case could add about 20% pressure. Not enough to make proof loads, but enough to give some pressure signs and beat up on the gun over time.

That said, within a headstamp it gets difficult to suggest a weight difference matters much to most shooting. However, it can indicate some kinds of defects or other problems. I once had a Lake City .30-06 case that was so heavy it felt funny to handle. About 35 grains heavier than others. Looking inside, I found it had a dark patch at the bottom. Probing, it felt like a lump, so I stuck a dental pick in and retrieve a misshapen piece of bullet core lead that had fallen in. So in that case there was inspection value in weighing the case.

[Gary Wells]

just curious, but are you guys that weight cases trimmikng all cases to an equal length?

[PACraftsman]

When you are comparing volumes, are these cases that are already sized and trimmed ready for loading?

[Metal god]

are you guys that weight cases trimmikng all cases to an equal length?

Yes , they are fire formed and trimmed to same length before testing .

are these cases that are already sized and trimmed ready for loading?

No and yes , They should all be fire formed to the same chamber . Sizing dies differ and the amount of shoulder set back can effect the case volume . If the cases are not the same length then the amount of water they hold can be different .

[Dufus]

All of my brass is old. I acquired most of it in the 60s with some being purchased in the early 70s.

I cannot load Rem brass to the same levels as I can WW brass.

Internal volume CAN make a big difference.

Remember, I am speaking of older brass cases, not newly manufactured.

[Unclenick]

That's for two different reasons. One is the old Remington brass had less volume by about 5-10% IIRC. The second is that Remington uses a brass alloy with more copper and less zinc, so it isn't quite as tough, though, loaded within its limits, it will probably last through more reloadings. Everything's a trade-off in some degree.

[firewrench044]

T.O'Heir --
You are wrong
It does make a difference
my group sizes decreased 10 to 20% in size and
that translates to higher scores ( with no fliers )

Gary Wells --
( I am OCD about case length )
to sort cases all case prep work is done
primer pockets, flash hole, sized, trimmed, annealed and recleaned
with wet SS pins so I weigh only case and no carbon
cases are from same year and batch number if possible
to eliminate any difference in cases
( in competition I will fire 80 rounds for score and 15 sighters
200, 300 and 600 yards, 1 competition per month plus the
same number of rounds for practice once a week, so I need a
lot of cases to work with )
Competition
( 3,500 3006 LC cases are same year )
( 3,000 308 Lapua cases are same batch number )
( 2,500 223 cases LC same year )
Hunting
( 308 Fed.350 cases just same brand (range pick ups)( they will be left where
they were fired))
(8mm Mauser 300 cases(purchased) same batch number
( they are left where fired)
( no 223 hunting, in Florida it is not legal to hunt deer with a 223)

[Jimro]

There comes a point of diminishing returns. What type of shooting you are doing is really going to determine when you decide something is "good enough" or "not good enough."

I do not sort LC brass by anything except headstamps to group my reloads into year consistent lots. I routinely turn out sub MOA ammunition this way.

My belief is that once my loads are under a minute, then the effort I would need to spend getting them to under .75 MOA or .5 MOA is time wasted compared to getting more trigger time or other practice. In High Power, the scoring rings are pretty generous, and the score difference between a 1.0 MOA lot of ammo and a 0.75 MOA lot of ammo is zero as long as the shooters are equal skill in equal conditions.

Since there never is equal skill and equal conditions, some folks spend the time making the absolute best ammo they can. But I I've shot enough to know that shooting in the wind at 500 or 600 is my limiting factor on scores, not the 200 or 300 yard line strings.

Also, all of my service rifles are using factory chambers, some in 5.56 and some in Wylde, and I expect my ammo to perform about the same across Colt, Krieger, Criterion, and Anderson barrels. And it does, right under a minute to slightly over a minute in the Colt HBAR that is getting up there in round count now.

I will point out here that brand new Mk262 Mod1 milspec match ammo generally groups between 1.0 MOA and 1.3 MOA in lot acceptance tests. This is great ammo. And while it is tempting to try to shoot smaller groups, the "flyers" that open up the groups to just over MOA show up in the group as the round count increases. This is why 5 shot groups are better than 3 shot groups, and I like to use 10 shot groups to validate a zero on a service rifle.

So, if your goals are modest, and your shooting discipline more focused on shooting technique than reloading technique, it is perfectly fine to not sort brass cases by either weight or volume. Obviously this wouldn't fly with benchrest, or even some F class shooters. But for High Power service rifle and hunting ammo, I wouldn't bother sorting by weight or volume.

Jimro

[Metal god]

I don't sort my cases by case weight or case volume either , WAY to much time and effort in that . Although I have and do from time to time weigh my cases and check case volume . How ever that's to see why one good charge/load worked in one lot of cases and not another . I use a lot of LC case in both 223 and 308 . I've not done much if any case volume test with 223 but have done some with 308 . As you can see with my numbers above . There's not much difference but I can say that the same load in my LC-14 cases does not shoot the same in the LC-10 cases and vice versa .

[FrankenMauser]

That statement (original quotation) is absolute garbage, in my opinion.

Even in .30 WCF (".30-30"), I've seen as much as 8% velocity difference between different lots of same-brand cases.
Even at 50 yards, that results in different points of impact.

And that's not even getting into what I've seen with .270 Win, .30-06, and .243 Win...


Volume arguably matters more than weight, but weight sorting (typically to 0.1 or 0.2 grain) has shown a difference in my loads. ...As mentioned before: Even in .30 WCF - a cartridge universally derided as inaccurate and not worth spending time 'accurizing' - it has proven well worth my time.


I can't even comment on other replies at this time. That quotation is so ridiculous, in my experience, that I honestly cannot believe it was published.

[Jimro]

FrankenMauser,

I don't disagree with your assessment, but I have to question whether the point of impact differences would have ruined a hunt. Being two inches off at 50 yards is a four minute dispersion, but inconsequential if you are hunting deer.

A 4 minute load is still better than some Federal factory ammo I've shot which came in at 8 inches spread at 100 yards. Not pretty, I thought there was something wrong with my rifle, but no, the rifle and scope were fine, just crappy factory ammo.

Dan Newberry's experiment with three different case brands still producing ammunition that shot sub MOA at distance using his OCW load up method seems to support the conclusion that at some sweet spot you don't need to sort cases to get good accuracy. Empirical evidence points out that if you aren't in that sweet spot, every little inconsistency adds up to group dispersion.

Of course Dan's experiment was with his lot of powder being shot through his rifle. Our mileage may vary.

Jimro

[FrankenMauser]

I understand, Jimro.
And it does depend upon the cartridge, rifle, components, and application.

But the load I cited, in weight-sorted brass, shoots 0.350" to 0.540" at 100 yards in a 16.25" Marlin 336, if I do my part with a good scope.
It doesn't matter which brand and lot of brass I use (other than velocity and trajectory being changed).
Group sizes remain small and predictable.

When you start with something like that, introducing a four-minute deviation is disastrous.
For hunting paper, four minutes is bad.
For hunting game, it's even worse, in my opinion.
I cannot, in good conscience, launch a bullet at a big game animal with the expectation that it will hit somewhere in a four to eight inch hit box, when a little time weight-sorting brass means that's a 0.5" to 1" hit box.

There are enough variables in the field that can work against the precision of a load. If I can eliminate one or more at the reloading bench, I will.



Probably five years ago, now, I tested weight-sorted R-P brass for .270 Win.
I know I posted about it here, but can't find the thread or details now.
Three hundred (five hundred?) cases were fully prepped and then sorted by weight into 0.1 gr lots, with the extreme ends of the spectrum combined into a single lot.
A 20-round box of brass from the middle of the bell curve was put up against the extreme weights box (20-round), with a load that averaged a bit under 0.400" at 100 yards in my Ruger 77 Mk II.

The mid-range box did what it was supposed to.
But the extreme weights box printed a scatter-plot group just shy of 2.5", if I remember correctly.
(That load was developed in R-P brass and has never been tested elsewhere.)


However...

I am more than willing to admit that I have found instances where weight-sorting doesn't really matter; and have cartridge where I simply haven't even tried.
Two examples:

Though I sort all R-P, WIN, and Federal brass for .30-06, I have found that it's a waste of time for Lapua (no surprise) and certain years of LC. My preferred LC .30-06 cases are LC 67, followed closely by LC 69.
Both lots that I have are fantastically consistent, and could probably be mixed without impacting performance enough for me to care.

With the 6x45mm, I stick with Hornady and PPU brass (easy to sort out of the other .223/5.56 cases). Other than just throwing a few cases across the scale out of curiosity, I have never bothered weighing them, let alone sorting beyond head stamp. I think I have five established loads right now, and the worst of them, actually a 'medium game' load, shoots about 0.6" at 100 yards.
I don't need to be ultra-precise with that rifle and cartridge (it's just for varmints and 'medium game'), and it's good enough for my standards as-is; so I'm not going to rock the boat by chasing more precision.



If one never sorts, then one will never know if an improvement could be found.
If one does sort, and finds that there is no notable improvement, then it may not be worth one's time.
And if one does sort, and finds a notable improvement, it is very difficult to give it up and return to "good enough".

The only way to know is to try it.