Weight Sorting Brass

[yukonal]

I sorted 100 Lapua .223 cases and they range from 95.3-96.2 grains (by weight, not volume)

I separated them--50 at 95.3-95.7, and 50 at 95.8-96.2 grains.

Am I being too fussy? is the 9/10 of a grain difference in weight with the whole batch so small...that it won't really MAKE a difference?

What is the general rule for case weight difference-in a batch of brass-that you sort, for say...small cases, med cases, and larger cases--like 7 Rem Mag? Thanks!

 

[markr]

There are several opinions on weight sorting. What kind of rifle and what kind of shooting do you do? Weight sort when new or after fireforming/neck turning/primer pocket uniforming/trimming? If you are shooting a rack grade rifle then your brass is fine as is, in my opinion.

 

[yukonal]

The brass will be used for F-TR, in a bolt action rifle. It has been trimmed, uniformed, and fired twice during fireforming/load developement. This will be the third loading of the brass, and I have my load. Ready to get serious. ;D

 

[alf]

The true test would be to keep them separated, and do a side by side shoot off.

Betcha don't see a difference.......

 

[Leaddog]

Case sorting by weight isn't nearly as accurate (or maybe not accurate at all) as case sorting by capacity. There is just too much variance in case head weight. Use at least 91% alcohol as your weighing medium.

 

[Wolfdawg]

I have posted this question before in reference to sorting by volume.
What do you use to PLUG the flash hole???
Wouldn't that material varry in weight? Unless you use the same item in every case (spent primer, putty, etc), how can the weight be accurate?

Wolfdawg

 

[jimbires]

I have posted this question before in reference to sorting by volume.
What do you use to PLUG the flash hole???
Wouldn't that material varry in weight? Unless you use the same item in every case (spent primer, putty, etc), how can the weight be accurate?

Wolfdawg

wolfdawg , I'm not a match shooter , so I just let the old primer in . this is accurate enough for me . I weigh the fired case . then I fill it . then I weigh it again . subtract the empty weight from the filled weight , this gives you the weight of the liquid . doing it this way the weight of the plug doesn't matter . Jim

 

[yukonal]

The true test would be to keep them separated, and do a side by side shoot off.

Betcha don't see a difference.......

I'd imagine you've done it a hundred times. So if you say I won't see a diff...I'll just load 'em all up and play.

 

[XTR]

The brass will be used for F-TR, in a bolt action rifle. It has been trimmed, uniformed, and fired twice during fireforming/load developement. This will be the third loading of the brass, and I have my load. Ready to get serious. ;D

Unless you are already shooting in the 190s you are wasting your time. Load them up and shoot. F class is not BR, you don't get extra points for group size. As long as it's holding .5MOA of vertical you'll never lose a point to the brass, on the other hand the wind is going to take fifteen or twenty a match for a while probably more on those days that the conditions get hairy. Until you get more practice you don't need to worry about it, and even then I don't think it matters in the game we play.

My unsorted WW brass will hold X ring vertical at 600 and about the same at 1000. Trust me on this one. If I lose points to vertical I can usually tell it was me. Maybe once a match I get a 9 that I wonder how it got there.

 

[RStewart]

The brass will be used for F-TR, in a bolt action rifle. It has been trimmed, uniformed, and fired twice during fireforming/load developement. This will be the third loading of the brass, and I have my load. Ready to get serious. ;D

Unless you are already shooting in the 190s you are wasting your time. Load them up and shoot. F class is not BR, you don't get extra points for group size. As long as it's holding .5MOA of vertical you'll never lose a point to the brass, on the other hand the wind is going to take fifteen or twenty a match for a while probably more on those days that the conditions get hairy. Until you get more practice you don't need to worry about it, and even then I don't think it matters in the game we play.

I don't weigh my brass and shoot a .223 in the low to mid-190's in FTR. When I consistently stay in the mid-190's I may start weighing brass. But like said above if you hold 1/2 moa vertical, I would be more concerned with the wind.
Good luck!

 

[yukonal]

Thanks guys, I'll just load 'em up and not sweat it.

Last week I had a .340" vertical at 200. Horizontal was .950" in a 15 mph wind. Before I even thought about sorting...just trying to not leave any stones unturned.

 

[ronemus]

I did an experiment several years ago to determine just how much effect brass weight has on .223 loads. I used WW brass (sized, trimmed and deburred, primer pockets uniformed, flash holes deburred, and neck turned) , WSR primers, charges of RL-15 or N-550 powder weighed to 0.1 gr, and 75 gr A-Max bullets. Using the lightest and heaviest cases (sorted from 1000 once-fired I had on hand), I had two lots of 10 cases with a 3 gr difference in weight. The average muzzle velocity difference was 16 fps, just a bit more than the 12 fps due to 0.1 gr of powder. I choose to sort 0.5 gr lots of brass for my long range loads, but the effect will only matter at 800-1000 yards - the vertical displacement on the target from such a small velocity change is negligible at shorter distances. Unless you control all other sources of variation, the effect of brass weight is negligible.

 

[Hermantk]

Unless you are already shooting in the 190s you are wasting your time. Load them up and shoot. F class is not BR, you don't get extra points for group size. As long as it's holding .5MOA of vertical you'll never lose a point to the brass, on the other hand the wind is going to take fifteen or twenty a match for a while probably more on those days that the conditions get hairy. Until you get more practice you don't need to worry about it, and even then I don't think it matters in the game we play.

My unsorted WW brass will hold X ring vertical at 600 and about the same at 1000. Trust me on this one. If I lose points to vertical I can usually tell it was me. Maybe once a match I get a 9 that I wonder how it got there.

As an F-class shooter, I have to disagree. If your POI is exactly halfway between the left and right sides of the bull, then 0.5MOA up or down will make no difference. BUT the further you get from that center line, the less vertical room you have. So if you are, say 0.4MOA south of the waterline and just a bit to the right or left of the north/south centerline, you will have an inner instead of a bull.

 

[dstoenner]

wolfdawg , I'm not a match shooter , so I just let the old primer in . this is accurate enough for me . I weigh the fired case . then I fill it . then I weigh it again . subtract the empty weight from the filled weight , this gives you the weight of the liquid . doing it this way the weight of the plug doesn't matter . Jim

Why don’t you just put the empty onnthe scale and zero that. Then fill the case. Weigh again and you have the direct volume with no math.

rinse and repeat

David

 

[memilanuk]

@Hermantk any particular reason for digging up a seven year old thread?

 

[USMCDOC]

When i was a real active Highpower long range shooter and using exclusively the .223, i was weighing my brass from the heaviest to the lightest and shot it in that order..

 

[The boogalorian]

@Hermantk any particular reason for digging up a seven year old thread?

It's a slow Tuesday.

 

[USMCDOC]

@Hermantk any particular reason for digging up a seven year old thread?

Well obviously, it has some relevance for him.. sometimes it is better to bring up an old one then to start a new one, if the info in the old one still has relevance and importance to it.. not defending him, but in the same time.. i don't like it when i see someone jump on someone for bring up an old thread.. that's just the way i see it..

 

[memilanuk]

...and if you read his post, he'd not asking a question, or anything else that suggests that it has a special significance to him.

I get it, people do a search on a particular subject, start reading threads, and get caught up in things and lose sight of the actual date of what they are replying to. It's always a slippery slope of what is and isn't 'too old'... few months? A year? Two? Five? Seven is generally over the limit, regardless of who you ask.

I understand what you're saying... but the flip side is, if no one ever says anything, the situation never gets any better.

 

[JimSC]

after the third beer a person might have a hard time remembering whether the thread he was reading was found in a search or was on the first page and get caught up in the spirit, not that I would have ever done such a thing.........

but in the spirit of things since it has been bumped

seems to me in a rough comparison of pressure difference between a fraction of a ml of case volume compared to the volume of gas produced would be too miniscule to matter when you are generating 50K psi.

Anyone know what the volume of gas is produced by a grain of powder is on average ? Should be pretty close across the board with burn rate being the major difference