For those who sort primers....

[TommyD11730]

I have posted this before, but maybe it still has some value to folks pondering sorting primers and what value it may have for their shooting discipline.
CW

That's a good read. Thanks for sharing.

 

[ELR LVR]

In the video the primers were only weighed in grains rather than grams but it does support the idea that primers of consistent weight will produce more accurate loads.
As myself and others have suggested, weighing in grams is much more accurate and able to determine weight variance to a finer degree and if his primer weight had been in grams with a variance of say .002 grams his target results would have been showing even better results.
Here is a better video explaining the variance that can be seen with the difference between primer weights:

and this follow up:

Thanks for the recommendation of weighing in Grams
(Actually milligrams)
Grams didn't make sense to me when grains is a finer measurement
But when I realized you must have meant milligrams it all made sense then
So I broke out my Gemini 20 - nice little scale I bought years ago
The batteries are still good even, cant believe it, nice blue backlit display, stays zeroed, doesnt drift.
Anyway, it has several different scales but the finest resolution is in Carats, or milligrams
---
Opened up a WHOLE NEW WORLD compared to weighing in grains.
---
Biggest Eye Opener is
There is good reason to pay more for MATCH primers like GM-210 and BR-2
More useable primers of the same weight and less outliers
BR-2's were nearly all the same weight, amazing!
---
Another eye opener - my 115 DTACS are WAY closer together in weights than Bergers
Maybe 5 mg spread for 50 bullets with 3 extreme outliers out of a quick 50 that I sorted
Some BENCHREST Bullets are not much closer in charge weights than normal brands like
Sierra
Lapua Scenar 6mm 105s' were all over the place, very disappointed in those
Some other brands are like 30 miiligrams apart for the same bullet!!!
WOW,
------
Anyway
Q. I am sorting bullets to within 5 milligrams (+/-2.5 mg)
and Primers to within 3 milligrams (+/- 1.5 mg)
do you believe this is close enough spread to batch them in?

 

[kiwijohn]

Yes to individually. It can go pretty quickly, if you set up what you need ahead of time. I place the primers to be weighed in front of the scale and use my RCBS primer flip tray to get them in a single layer, one sleeve of 100 at a time. I then put 4-6 cups on each side of the scale. Using tweezers, I put a primer on the scale and read the weight. Then I put a second primer on the scale, taking the first off and into a labeled cup of that weight, then read the weight of the second primer. I put a third primer on the scale and put the second into its weight cup, and so on. This minimizes movements to the scale. Forgot the weight? put it back on the scale like you had just grabbed it from the unweighed pile. I can do 1000 in under an hour this way. I also re-zero the scale every 100 primers.

How do you know if your scale has drifted? I used to weigh stuff this way as well, its economic on movement. But I changed to single on check zero use.

 

[64Rambler]

How do you know if your scale has drifted? I used to weigh stuff this way as well, its economic on movement. But I changed to single on check zero use.

One, I leave the scale turned on, this keeps drift at a minimum. Two, I calibrate at the beginning of every weighing session. The FX 120i is only 3 decimal places, but I have balances at work that go to 5 and my 100 g reference is 100.00002 g. Three, for long weighing sessions like sorting a case of primers (5000), I check the reference every 1000 primers, and if it's off more than 0.001 g, which it usually isn't, it gets recalibrated. Four, I have a ground wire from the ground pin on the next outlet over from the scale in contact with the opening of the stage on the balance. When I start a weighing session, I touch the bare end of the wire bringing me to the same potential as the scale and re-touch it frequently in the process of putting the cup in and out. This has been the biggest improvement in "drift" as it kills the fluctuation seen due to static. Even after sitting for several weeks recently, the calibration weight came in at 100.002 g, but it is typically 99.999 to 100.001 when used frequently; that's plus or minus 0.02 gn, or one kernel of N150.

 

[Mulligan]

---
Another eye opener - my 115 DTACS are WAY closer together in weights than Bergers
Maybe 5 mg spread for 50 bullets with 3 extreme outliers out of a quick 50 that I sorted
Some BENCHREST Bullets are not much closer in charge weights than normal brands like
Sierra
Lapua Scenar 6mm 105s' were all over the place, very disappointed in those
Some other brands are like 30 miiligrams apart for the same bullet!!!
WOW,
------

I am mostly a mid range benchrest shooter (600 yards). In my testing small differences in bullet weight could not be seen on target at 600yards (the distance I have most readily available to test at). Sorting by OAL of a bullet is far more significant on target than most any other measurement I have tried. If using customs, I stop there. If there is a chance (factory made projectiles) bullets for more than one point-up die made it into the box, I will short until the cows come home. For example, Berger 105 VLD hunting bullets and 105 Hybrids will run shoulder to shoulder with any of the customs, if sorted, and shorted at least once more. Where as with customs, MOST of the time, one sort is all you need. I now roll my own, and yes, I still short by OAL.

CW

 

[ELR LVR]

I am mostly a mid range benchrest shooter (600 yards). In my testing small differences in bullet weight could not be seen on target at 600yards (the distance I have most readily available to test at). Sorting by OAL of a bullet is far more significant on target than most any other measurement I have tried. If using customs, I stop there. If there is a chance (factory made projectiles) bullets for more than one point-up die made it into the box, I will short until the cows come home. For example, Berger 105 VLD hunting bullets and 105 Hybrids will run shoulder to shoulder with any of the customs, if sorted, and shorted at least once more. Where as with customs, MOST of the time, one sort is all you need. I now roll my own, and yes, I still short by OAL.

CW

Thank you much!
Thats great info

 

[kiwijohn]

One, I leave the scale turned on, this keeps drift at a minimum. Two, I calibrate at the beginning of every weighing session. The FX 120i is only 3 decimal places, but I have balances at work that go to 5 and my 100 g reference is 100.00002 g. Three, for long weighing sessions like sorting a case of primers (5000), I check the reference every 1000 primers, and if it's off more than 0.001 g, which it usually isn't, it gets recalibrated. Four, I have a ground wire from the ground pin on the next outlet over from the scale in contact with the opening of the stage on the balance. When I start a weighing session, I touch the bare end of the wire bringing me to the same potential as the scale and re-touch it frequently in the process of putting the cup in and out. This has been the biggest improvement in "drift" as it kills the fluctuation seen due to static. Even after sitting for several weeks recently, the calibration weight came in at 100.002 g, but it is typically 99.999 to 100.001 when used frequently; that's plus or minus 0.02 gn, or one kernel of N150.

Thanks for the explanation, I like the trick with the earth wire. My plug pack doesnt have an earth, but I imagine by creating an earth strap I can bring the static levels down some, I might invest in a static mat. I find I can get small drifts with the Fx300, this may help with that.

 

[Rwfish]

New to this game so I spent some time during this summers matches sorting my primers for loading. While the deviation is minimal when reading in grns (for short range benchrest / score) I really saw little to no difference on target. Last week I pulled aside 5 primers (Federal Match GM205M) weighed each and then broke down the component weight after dissolving the primer paste out. Then used the difference to calculate what the paste weight was. Small sample but it’s obvious that a heavier primer doesn’t always mean more powder in all cases. Again, if I had a scale that went out another decimal and measured in milligrams with a larger sample size it may seem more significant. My thought is In sorting 100 primers I’d probably pull out the significant highs and low weights and load the remainder for score shots…

 

[64Rambler]

I don't think weighing in grains is a waste of time. On the A&D FX120i you will get 3 significant figures for the weight of a primer, regardless of which unit the scale is set for, as Tom pointed out.


Will there be a difference in the piles? Yes, but only slightly and only because of where the scale rounds up to the next digit. 0.02 grains is 0.00129598 grams. Digital scales, regardless of the units set, have additional decimal places internally that are not displayed so that what you see is the rounded number.
And if you forget to switch your scale back to grains for powder, that first charge is going to be a doozie!

Following up on this, I broke into a new case of 5,000 and pulled a sleeve. Personally, I sort in 0.02 gn increments (the resolution of my scale), and it gives me a reasonable number of "buckets" to work with, but after seeing these results, I may switch to 0.002 gm buckets. For those that weigh-sort in grams, do you group in 0.001 gm increments? 0.002? 0.003?
Here's what I found with a single sleeve of 100;

 

[LRPV]

I weigh with a Sartorius Entris-64, it goes .001 grains. I just sort in grains to the hundredth IE 3.79, 3.80, 3.81. I ignore the .001 weight number because it fluctuates so much it would take me forever to decide which pile to put it in. I'm not sure how much difference there would be side x side using a .02 FX120i vs a .001 Sartorius but for what I am doing, I feel like I am doing good by grouping to .01 grains anyway and I know guys that are shooting very well grouping them by .02 grains.

I am still having a hard time wrapping my head around how a scale that is accurate to .02 grains is magically somehow MORE accurate when switched to grams.

I'm not trying to say anyone is doing it wrong or anything like that, I just don't understand it, so I'm trying to learn. I have seen guys alluding to the fact that grams is somehow a more accurate measurement which I can't wrap my head around.

.02 grains = 0.001295978 grams so is it the finer number breakdown of the sort with grams that you guys are liking or is there something I'm missing here?

 

[quest450]

I thought that gram is finer resolution than grain and I do weigh my primers in grams, it's been a looooong while since my last math class so I could be wrong, I just calibrated my FX120 and try both grams and grains

0.239 grams = 3.70 grains (same primer weighted)

You can't go wrong either way I guess but I'd like to know who's the king of finer resolution grain or gram.

 

[quest450]

Found a primer that is 0.238 grams = 3.66 grains that lead me to believe that grains is the King of the hill, I guess I was wrong....Thanks Jason !

 

[LRPV]

So you can get a finer sort (more piles) in grams then, right? Doesn’t mean the scale is weighing to a smaller weight just able to break down to smaller divisions in gram mode.
Right?

 

[quest450]

I think you'd get "more piles" in gram mode

0.238 and 0.239 that's two piles

3.70 and 3.66 grains would make four piles therefore finer resolution at least in my Polish math

 

[Straightshooter1]

Following up on this, I broke into a new case of 5,000 and pulled a sleeve. Personally, I sort in 0.02 gn increments (the resolution of my scale), and it gives me a reasonable number of "buckets" to work with, but after seeing these results, I may switch to 0.002 gm buckets. For those that weigh-sort in grams, do you group in 0.001 gm increments? 0.002? 0.003?
Here's what I found with a single sleeve of 100;

Though I sort by .02 gr (the resolution of my scale), I simply don't find that there's any difference in performance from one batch to the next in weight. So, I don't think it really makes any difference whether you're measuring in grains or grams. What you don't want is having the far ends of the weight range (the lightest and the heaviest) mixed together as that's where you'll see a difference. Like out of 1,000 LRP, I'll have the heaviest at 5.54 and the lightest at 5.18.

 

[Leo_B]

Grain is a smaller measurement. If you measure down to one gram difference that is ~15.4 grains difference. So if you measure down to 1 grain difference that is ~15 times more accuracy than measuring in grams.

 

[quest450]

Well allrighty then, for the next Rendezvous I'm switching my scale to grains to weigh my primers.......LOOK OUT !!!

 

[JFrank]

For myself, there was less scale drift in the gram mode using a strain gauge scale. I’ve since moved to the fx120 yet kept the gram mode for sorting.

 

[Fire Dog]

Grain is a smaller measurement. If you measure down to one gram difference that is ~15.4 grains difference. So if you measure down to 1 grain difference that is ~15 times more accuracy than measuring in grams.

The grams people are talking about is using that weighing setting on the scale and that is much finer than weighing in grains..
The gram setting on your scale will allow you to weigh to .0001 grams, ie .1 milligram.
A very small weight indeed. One grain = 64.799 miligrams

 

[WSnyder]

The grams people are talking about is using that weighing setting on the scale and that is much finer than weighing in grains..
The gram setting on your scale will allow you to weigh to .0001 grams, ie .1 milligram.
A very small weight indeed. One grain = 64.799 miligrams

Same thing has been and can be done when weighing powder. I set the Autotrickler target in grains in the app then switch the scale to grams. Finer resolution.