Weight Sorted Primers - OR - Now My Back Hurts

[Rocketmandb]

I just finished spending an inordinate amount of time at my bench weight sorting about 1000 BR-2 primers. I've never done this before, but I am going stir crazy and I'm sure it affected my mind somehow.

The good news is that I'm set for a while.

The bad news is that my back hurts.

I chose an "acceptable" range of 5.20 - 5.28 gr, all others were outsorted for use as foulers, fire-formers, etc. I did not record weights for all primers, but did do so for one box of 100.

In the 100:
Average weight: 5.22 gr
In range: 71
SD: .04 gr
Min: 5.08 gr
Max: 5.30 gr

In the overall sample:
Min: 5.06 gr
Max: 5.36 gr

Based on this chart, I should have kept 5.18 to 5.26, but I based my range off my early measurements, and they skewed a bit high. Also, I was somewhat surprised at the spread - in the overall sample, it's .3 gr. In the 100, it's .22 gr.

Next step will be to compare the performance of the "in" bin with those in the "out" bin. I'm also probably going to do a smaller amount of 215Ms and BR-4s.

 

[Steel head]

 

[Rocketmandb]

View attachment 7290380

Scoff if you will. It was either do this or spend time with... I'll stop there before I get in trouble.

 

[SnowMan]

I would try drinking. It is infinitely more beneficial and your back won't hurt as much.

 

[cropdude]

I will more than likely not spend the time that you did, but I am sure hoping to see your comparison when you get it done.

 

[Steel head]

Scoff if you will. It was either do this or spend time with... I'll stop there before I get in trouble.

Lol!

I understand now,,,,,carry on.

 

[phlegethon]

Someone needs to develop an open source brass handling robot, perhaps arduino based. Then we could automate stuff like this.

 

[Dthomas3523]

But do you have a competition primer seater to test primer anvil compression after this?

 

[Steel head]

But do you have a competition primer seater to test primer anvil compression after this?

 

[phlegethon]

But do you have a competition primer seater to test primer anvil compression after this?

What about measuring and sorting by the length of the flash hole? ?

 

[Mike Casselton]

And then we get into do you weigh cases before or after doing all the prep work.

Then there's powder drying.

Oh, and weight vs volume powder charges.

Bullet bearing surface measurements.

Meplat trimming. (Do you weigh before or after trimming here too?)

Bullet force seating guages.....

Drinking booze sounds a lot better and I don't even like the taste of hard likker..

 

[zeroz]

 

[DIBBS]

I was gonna ask why... but unnecessary at this point.

 

[Rocketmandb]

So, for shits and grins I loaded 10 rounds using the weight-sorted primers, and 10 using the outsorts. Unfortunately, or fortunately, depending on your point of view, I got my new 300 PRC, so didn't get to shoot them until today. I also loaded 20 rounds of my first 50 of virgin ADG with outsort primers and compared them to the weight-sorted primers.

New Rifle/New Brass:
Outsorted SD: 7.8
Weight-Sorted SD: 6.5

Original Rifle/Brass:
Outsorted SD: 7.2
Weight-Sorted SD: 6.2

 

[Jayjay1]

I´m exactly with you?

That´s why I´m turning, trimming, chamfering and deburring my primers, as well as I´m sorting them by odor and I have no idea and can´t understand why not everybody is doing this.

 

[Buckley]

I’ll take your culls! Based on your chart above in guessing at least 300/1000. You can’t possibly need that many foulers!

 

[Gustav7]

And then we get into do you weigh cases before or after doing all the prep work.


Drinking booze sounds a lot better and I don't even like the taste of hard likker..

LIQUOR?....I HARDLY KNOW HER!

 

[morganlamprecht]

So, for shits and grins I loaded 10 rounds using the weight-sorted primers, and 10 using the outsorts. Unfortunately, or fortunately, depending on your point of view, I got my new 300 PRC, so didn't get to shoot them until today. I also loaded 20 rounds of my first 50 of virgin ADG with outsort primers and compared them to the weight-sorted primers.

New Rifle/New Brass:
Outsorted SD: 7.8
Weight-Sorted SD: 6.5

Original Rifle/Brass:
Outsorted SD: 7.2
Weight-Sorted SD: 6.2

when ive compared in the past, in a few different cartridges (all short action / standard bolt face)...comparing lighter primers vs heavy, i saw .1gr of primer weight was consistently worth ~10 fps average increase, if i remember correctly...been years tho

SDs decreased slightly every time in sorted strings as well, but not enough that i sort primers ever lol

 

[Powder_Burns]

I’m sorting shoot n c’s by weight now.

 

[Steel head]

I’m sorting primer trays now.

 

[Milo 2.5]

There was a huge squabble on accurate shooter over weighing primers, I think a couple got banned and a couple guys left because of attitudes towards the theory.
It was funny, I laughed.

 

[Gustav7]

So, for shits and grins I loaded 10 rounds using the weight-sorted primers, and 10 using the outsorts. Unfortunately, or fortunately, depending on your point of view, I got my new 300 PRC, so didn't get to shoot them until today. I also loaded 20 rounds of my first 50 of virgin ADG with outsort primers and compared them to the weight-sorted primers.

New Rifle/New Brass:
Outsorted SD: 7.8
Weight-Sorted SD: 6.5

Original Rifle/Brass:
Outsorted SD: 7.2
Weight-Sorted SD: 6.2

This is pretty interesting but I have a question, mainly regarding the statistics of it all.

Wouldn't it be a more accurate test to the weight sorted with a fresh tray of primers that is not sorted in any manner?

In this case, the outsorted groups are the outliers on the extremes, which inherently makes them the highest amount of difference in any given tray of primers, but given a fresh tray of primers, its very unlikely that you'd get the extremes lumped together, especially when the "weight-sorted" primers make up 70% of the entire tray.

I feel like the actual SD of any given primer tray would be in the middle, or slightly closer to the weight-sorted SD. So for your New Rifle/New Brass workup, the true average SD would be something like ~6.8-7...

Am I wrong in this thinking?

 

[longshooter]

I've been sorting primers by brisance, but I think it's causing me to go blind...well, that and other things...

 

[Whiskey Tango Foxtrot]

Thanks...
This just helped me to decide NOT to get back into LR competitions!

 

[phlegethon]

This is pretty interesting but I have a question, mainly regarding the statistics of it all.

Wouldn't it be a more accurate test to the weight sorted with a fresh tray of primers that is not sorted in any manner?

In this case, the outsorted groups are the outliers on the extremes, which inherently makes them the highest amount of difference in any given tray of primers, but given a fresh tray of primers, its very unlikely that you'd get the extremes lumped together, especially when the "weight-sorted" primers make up 70% of the entire tray.

I feel like the actual SD of any given primer tray would be in the middle, or slightly closer to the weight-sorted SD. So for your New Rifle/New Brass workup, the true average SD would be something like ~6.8-7...

Am I wrong in this thinking?

You’re right, but he was also right to do the experiment the way he did. If we are not sure if there is any effect, then we want to set things up in the most extreme way so that we maximize the difference, if there is one. Since he found a small difference, assuming it is valid, we now have to realize that in practice it will be much smaller compared to normal unsorted primer use.

It may be something to consider if every other aspect of reloading is completely optimal, and you are shooting in a discipline where you can see the difference (and I think that would only be benchrest, F class, or ELR).

 

[Gustav7]

You’re right, but he was also right to do the experiment the way he did. If we are not sure if there is any effect, then we want to set things up in the most extreme way so that we maximize the difference, if there is one. Since he found a small difference, assuming it is valid, we now have to realize that in practice it will be much smaller compared to normal unsorted primer use.

It may be something to consider if every other aspect of reloading is completely optimal, and you are shooting in a discipline where you can see the difference (and I think that would only be benchrest, F class, or ELR).

Oh for sure, I wasn't meaning to protest the method for the initial testing, just making sure my thought process was correct.

It's interesting to see that such a thing as primer weight can have a difference, even if shooters don't end up doing it.

 

[Rocketmandb]

Wouldn't it be a more accurate test to the weight sorted with a fresh tray of primers that is not sorted in any manner?

Yeah, though I wanted to get more toward the extreme. As it stands, there is certainly a difference, but I'm not sure that what will amount to less than 1 FPS of SD is worth it.