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Discussion Starter · #1 ·
Anything wrong with weighing mixed range brass for a tad bit of consistancy that someone could think of?

this isn't $20,000 Bench Rest race chassis shooting i'm doing here so neck turning and cubic micrometers and concentricity and jump (it for an AR) isn't important. I am an accurate shooter and i've never sorted brass by weight or headstamp and i'm looking to get that little extra edge of consistancy from my hand loading. I've read and read and read about weighing cases and how if you're 2nd place in F-Class then yeah maybe give it some thought otherwise just load and shoot.

This would be all fine and dandy if i was just a range blaster, but i'm not. When i go out to shoot i'm surprised if i go through 90 rounds. when i pull the trigger, i expect to hear a *CLAAANG!* 3 seconds later (do the math, it's kind of a long ways to go for a .223).

The cases i've weighed (sized, cleaned, & trimmed) are mostly 5.56 NATO crap (PPU, IAI, LC, etc of all years) and most of them are coming in at 91.5 gr +/- 2 grains. PMP is well over 100 grains, and some of the commerical .223 comes in under 90 but for the most part falls in the 2 grain window. anything outside of that is pitched into the lightweight blasting bin.

is this to anal retentive? too loose a spec?
 

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I read on the interwebs that 5.56 has a thicker wall which will cause a bit higher pressure than a .223 case with the same powder charge.


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It's still sort of a guess. The brass weight can mean smaller/larger internal volume or not. If you want the most consistent brass, you need to weigh the internal volume using water or ball powder. Lots of things make brass diff in wt, thickness is one, but so is the extractor groove size, web thickness & rim thickness. I sort by headstamp & wt, close enough. IMO, same headstamp, same manuf process, so dimensions should be pretty uniform.
 

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Discussion Starter · #5 ·
i'm sifting through 30 years of .223/5.56 brass and each headstamp will be a bit different. Take any year Lake City... some will have 4 marks like this: (* * LC * *) some like this: (* LC * * *), some have 3, some go all the way around, some are opposing, some are asymetrical.... different machine lines kicking out the brass. i just want to get close.
 

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i'm sifting through 30 years of .223/5.56 brass and each headstamp will be a bit different. Take any year Lake City... some will have 4 marks like this: (* * LC * *) some like this: (* LC * * *), some have 3, some go all the way around, some are opposing, some are asymetrical.... different machine lines kicking out the brass. i just want to get close.
Sounds like lot to lot markings, not unlike LC09, LC10, etc. unless I was putting bench rest comp rds together, I wouldn't bother doing anything other than sort by head stamp. I would rather buy 100 Lapua cases for that though.
 

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It seems to me if all the brass is sized and trimmed to the same external dimensions, sorting by weight would get you pretty close on internal volume, regardless of headstamp. I'm sure this method is more consistent than my trigger finger.
 

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I'm with fred on this one, weight might get you close, but for the highest consistency, you need to match up headspace AND case weight, if you're not going to measure each case for internal volume.

I spent more than one evening teaching my 3 year old how to read headstamps with marked bins spread around to sort out my accumulated brass, lol.
 

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He's 4 now and I have him trained pretty well on how to resize/decap 45ACP brass on the Hornady LNL AP, he has to put his whole body weight into the up-stroke, but he's determined.

When my 7m/o gets to the same stage, I'll really be ready to take over the world with my two minions :)

On the subject though, I know if your brass accumulation is anything like mine, sorting out is a big, ugly chore staring you in the face, but if you go by case weight alone, you'll still have random internal shape and volume. Meaning you'll spend the time to weigh cases, and accomplish nothing.

I did all my sorting in stages, one big bin for anything LC, one for PMC, one for RP, one for "all other" from there I needed more bins and sorted out the LC by year, the PMC and RP's just stayed in their bin, as I didn't figure out a good way to sort them further, aside from weight or volume.
 

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Discussion Starter · #11 ·
the one thing i noticed was that the LC and PPU were all really close to each other in weight. IAI is usually 5 gr. heavier, and PMP is redonkulously heavy.

I'm not looking for cubic micrometer volume accuracy... that's for the 200 yard 6BR bench chassis competitors... I just need enough to get me 1/2 MOA with consistent low SD velocities.
 

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For 1/2MOA out of an AR, head stamp will be more consistent than case weight, and work up your loads using only one head stamp for your accuracy loads.
 

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the one thing i noticed was that the LC and PPU were all really close to each other in weight. IAI is usually 5 gr. heavier, and PMP is redonkulously heavy.

I'm not looking for cubic micrometer volume accuracy... that's for the 200 yard 6BR bench chassis competitors... I just need enough to get me 1/2 MOA with consistent low SD velocities.
Really knight, for that I would buy a box or two of Lapua, done. Most uniform brass I have seen in any caliber. Off a bench, you should be able to collect them all. My 20" hvy puts them in a neat little pile about 2ft from the bench. If you must, You can weigh cases before, fill with ball powder & weigh again, but very time consuming.
 

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Anything wrong with weighing mixed range brass for a tad bit of consistancy that someone could think of?

this isn't $20,000 Bench Rest race chassis shooting i'm doing here so neck turning and cubic micrometers and concentricity and jump (it for an AR) isn't important. I am an accurate shooter and i've never sorted brass by weight or headstamp and i'm looking to get that little extra edge of consistancy from my hand loading. I've read and read and read about weighing cases and how if you're 2nd place in F-Class then yeah maybe give it some thought otherwise just load and shoot.

This would be all fine and dandy if i was just a range blaster, but i'm not. When i go out to shoot i'm surprised if i go through 90 rounds. when i pull the trigger, i expect to hear a *CLAAANG!* 3 seconds later (do the math, it's kind of a long ways to go for a .223).

The cases i've weighed (sized, cleaned, & trimmed) are mostly 5.56 NATO crap (PPU, IAI, LC, etc of all years) and most of them are coming in at 91.5 gr +/- 2 grains. PMP is well over 100 grains, and some of the commerical .223 comes in under 90 but for the most part falls in the 2 grain window. anything outside of that is pitched into the lightweight blasting bin.

is this to anal retentive? too loose a spec?

At one time i weighed my brass, sorting by 1 grain, did some tests and found that merely sorting by head stamp was just as good.

don
 

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I read on the interwebs that 5.56 has a thicker wall which will cause a bit higher pressure than a .223 case with the same powder charge.


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Read some more. :cool: My loads generally shoot into one hole @ 100 yds, and I don't weigh any brass. 5.56 is the same, internally, as a general rule, as is commercial. AAMOF, some commercial brass is thicker than 5.56 brass.

A more consistent (sic) accuracy would be obtained by measuring distance-to-lands and experimenting with seating various distances off the lands.
 

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A more consistent (sic) accuracy would be obtained by measuring distance-to-lands and experimenting with seating various distances off the lands.
Yet in an AR, I find this just doesn't come into play much. You have a mag limit, load to that.
 

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and that's what i load to, mag limit 2.260. the jump is a little more than 1/10th of an inch.
I cheat a bit for reliability & load everything to 2.250". I did single load some long 75grA-max in my 20" hvy, shot sub moa, but then I am not going to single load my AR.
 
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