Weight sorted brass and ES

al...shooting or throwing ???
my test results of n133 and both 8208's is based on a large sample with a harrells.
notice i did not enclude any long range long stick powder
at the other hand i can load 4227 to the accuracy/sensitivity of the mx123...... plus or minus .03
mike in co
alinwa said:
Variability........oddly enough, in my testing ball powder is just as bad as stick.
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mike,

I recently had reason to load a couple thousand WSM cases. I tested a bunch of ball powders since these were hunting rounds and I wanted FAST and EASY so I figured I'd throw the charges. It didn't work out like I'd anticipated. I tried a bunch of the "magnum" and "magpro" and "magshot" and H380 and such against 4350, RL17 and the like and surprise surprise, the ball powder threw just as wacky as stick!

I used stick powder and the Chargemaster for the whole lot.

bummer

al
 
so big stick powder.....vs balll......hmmmmm
well in my limited experience, i try for a load that has a large window.....say .3 or .4 spread with the same accuracy..and then load in the middle for fast loading...but yes i try it out first, make sure the machine will in fact throw inside that spread...i have had no issues loading aprox 25 gr loads in a 223 with ball and short stick(aa2015)......my last big lot of 500...twice was rl15 and mil ball both for 308...again no issues once a reasonable load was found. i only load 4350 in 50 rd batches..so they get wieghed.

mike in co
 
Several years ago I did my own little test. Two big handfuls of both IMI and Win. new .223 brass........weighed them all, took the heaviest and lightest of each headstamp, and a range in between. Fired-trimmed-turned-etc, weighed again and marked the weight on each case. Then triple checked water volume. In neither headstamp did the lightest case have the biggest capacity. With IMI the heaviest case also had the most volume, Win. the heaviest had second or third largest volume. With IMI the internal water volume spread heaviest-lightest was only .3gr, Win. it was about .7gr. There was no correlation between case volume and weight. That was inexpensive .223 brass, and weight sorting hundreds of cases would accomplish nothing.
 
this is completely opposite of my test of one lot of 500 pcs. all win all from one lot.
spread was 89.6 to 94.5..a 4.9 gr spread...that is a 5% spread....to me, enought to worry about. volume spread was 29.9 to 30.6....0.7...a 2plus % increase.....
this was a very long bell curve. only 300 plus pcs were in a useable part of the curve.
...my guess...your lot/sample size was too small.
what kind of scale ???
two big handfuls..there is a technical term.

mike in co
Ackman said:
Several years ago I did my own little test. Two big handfuls of both IMI and Win. new .223 brass........weighed them all, took the heaviest and lightest of each headstamp, and a range in between. Fired-trimmed-turned-etc, weighed again and marked the weight on each case. Then triple checked water volume. In neither headstamp did the lightest case have the biggest capacity. With IMI the heaviest case also had the most volume, Win. the heaviest had second or third largest volume. With IMI the internal water volume spread heaviest-lightest was only .3gr, Win. it was about .7gr. There was no correlation between case volume and weight. That was inexpensive .223 brass, and weight sorting hundreds of cases would accomplish nothing.
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mike in co said:
....spread was 89.6 to 94.5.......volume spread was 29.9 to 30.6....0.7...a 2plus % increase..... [QOUTE]

So......I measured Winchester weight spread about the same, volume spread was identical. With IMI the weight spread was about twice as much, volume spread was less than 1/2 as much.

mike in co said:
...my guess...your lot/sample size was too small.
what kind of scale ???
two big handfuls..there is a technical term.

mike in co
Click to expand...

We've been through this before.

Sample size was fine.......my purpose wasn't statistics or bell curves or any of that stuff. I was looking for a good weight spread between heaviest and lightest. People sort new brass thinking it'll help accuracy. I wanted to find out if equal caseweight within a headstamp also meant equal volume. It didn't. I weighed maybe 50 cases of each headstamp, plenty to find heavy ones and light ones.....took those and a bunch in between.
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and again..it does not match my results.....volume did follow wieght variation.....to the point the one lot of thirty all the same wieght had the same volume.....it not a large volume but it did follow.
mike in co
 
The test results were inconclusive due to the failure of my Shooting Chrony model # sux1000. The low group had an ES of 12fps, the middle group had an ES of 951fps and the high group had an ES of 34fps. I don't trust the data due to middle group test results. I corrected the problem by ordereing an Oehler35 and will retest when time permits. The good news is Lapua has supplied me with 488 pieces of brass with a 1.0 grain difference from lowest to highest.

Eric
 
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