Sorting primer velocity with the Garmin Xero

[chevy_man]

What kind of brass, bullet, caliber?
I bet that's with Varget
That's tight !!

I don't think any 5 sequential shots (light or heavy) in the test had that kind of ES and SD.
Maybe the CCI450s are my problem.

25 Creed

Starline 6mm creed SRP brass
CCI 450
43.7grn 6.5 Sta-ball
135grn Bergers loaded to mag length.

Until I got the pressure high enough for everything to plateau, the extreme spread was 25-80fps.

 

[Rocketvapor]

The charge that produced the data in hlee's plots was 31.8 grains of SB6.5.
I have settled on a velocity over several range trips of just under 3000fps with the 85.5s.
Groups opened up if I went much over 3000.
I get about 12 to 15fps per tenth of powder.
To see if the plotted data, Velocity Vs Total Primer Weight, will hold I will load 31.6gr with 3.70grain primers.

Getting ready to do some sorting (3.700 grains).
Check weights 200mg, 30mg, and 10mg. I use ASTM Class 1 and 2 weights.
Using gram mode, low range on my EJ-54D2 gives me 0.0002g resolution (0.00309grains).
0.2398g +/- a count should do it.
I might even drag out the A&D ER-182A to spot check results.

 

[JoshPutman]

So, theoretically, if heavier primers make for higher velocity, one could figure out how many kernels of powder to subtract from cartridges loaded with them, and how many kernels to add to lighter primer rounds, to make them all even out.

 

[Rocketvapor]

Maybe,
I'm going to use hlee's curves to drop charge a little to 31.60 grains (15 rounds) and 31.70 grains(15 rounds) and go up to the 3.700 grain primer bin to shoot for 3000fps +/- a little.

I've been up to 32.5 grains of SB 6.5 with the 85.5s but groups opened up. There's probably another node up there somewhere above 3100fps.
Decided to come back down.

A science project and reloading all rolled into one.
Ain't this FUN

 

[memilanuk]

So... I'm just gonna put this out there: If you aren't already shooting clean, or very close to it - dropping one or *maybe* two points that are clearly elevation - sorting primers isn't going to get you where you want to go. If you're down 20-25 points for the day, at 600yds, you've got much bigger issues going on somewhere else in your loading (or gun handling) process.

I feel your pain - I've been there, with what seemed like random damn vertical fliers at times - but with the exception of *one* time, *one* screwy batch of CCI 450s that had a stupid high ES/SD and just fucked me over at a state LR championship... it's probably *not* the primers. Look elsewhere. For me, it was neck tension / friction.

Now, if you want to continue down this particular rabbit hole 'just because', or it genuinely intrigues you - I get that too. Nothing wrong with a little CDO behavior in this sport

 

[Doom]

@Rocketvapor

I've worked off and on as a test engineer for over 40 years so I hope my comments will help. It's a valid point that your test may not have perfect statistical validity but that doesn't negate the results of your tests results based on your loads. I was going to run some regression on the results but @hlee beat me to it. Your test definitely shows a relationship between velocity and and total weight and also velocity and weight loss. By testing at the extremes you reduce the influence of other variables by maximizing the effect of the variable of interest. I was amazed at the correlation with weight loss.

The take from your test is there appears to be a direct correlation between primer weight loss and primer weight. There is a strong correlation between weight loss and velocity and the total weight and velocity. There is an element of uncertainty here in that the assumption of weight loss is proportional to pellet weight is something that may not be correct but appears to be the case. A hypothesis can be made that there is a direct correlation between primer weight and velocity and pellet weight loss and velocity and primer pellet weight and total primer weight. It would require additional tests to prove that hypothesis and what range of primers and calibers/powders/cases/etc it may apply to.

Just for the record, when I originally saw this thread I did not believe that you would be able to show the correlations that are here.

 

[Rocketvapor]

Thanks.
I guess since the number of extreme outliers is small within a brick of primers many just won't run into speed issues.
I did ON PURPOSE by testing the way I did. Measuring stuff is a hobby now that I'm retired after decades of calibrating government test equipment.
Done with tests for a while, sort of (see the pun?)
I was going to sort out about 40 3.700grain primers but it turns out I have to open the window to get enough primers that I have left to test. Have 40, individually recorded, from 0.2394g/3.695gr, to 0.2402g/3.707gr. Weighed in gram/low range with 0.0002g resolution. 40 totaled 9.594g/148.06gr on a A&D ER-182A for an average of 0.2399g/3.7022.

Guessing at powder charge I'm going with 2.051grams/31.652grains.

It will be about a week before I can go shoot these (looking for better groups).

I agree that this adds a lot of time to reloading prep. Sorting isn't terrible with a good scale, but recording the data takes most of the time. I mostly do it for fun. Might be tough to tightly sort primers with a milligram scale.
The Garmin Xero helps

 

[chevy_man]

That makes more sense now.

Like an old guy I know that died with hundreds of boxes of cheap 22lr sorted into rim thickness.

Just bored and can't watch TV

 

[Rocketvapor]

I know people search for the perfect powder, charge weight, seating depth, neck tension maybe even primer brand, but wouldn't it be cool if something like this exists?

This did NOT happen.

 

[JerkyFreak]

Maybe redo the test with an extruded powder.

Also try repeating the test but with standard primers.

I suspect that the difference between heavy and light won't be nearly as much as you think.

 

[Rocketvapor]

All good suggestions from everybody.
Was up late last night and thought of this.
Primer Orientation might make a difference.

The Primer Weight test is open for anyone else to duplicate.
I'm just gonna shoot the already sorted bins to finish up this brick.

 

[Rocketvapor]

Well, off the primer sorting quest for a while, loading some for the wife.
Previous trip she shot 20 shots then quit, Sinuses.
10 with WIN41 Primers and 10 with CCI450.

Flo 3/21/24 Savage 22N
CCI 450 3.66gr 31.8gr SB6.5 85.5
10 shots
min 3002.3
avg 3018.2
max 3033.1
ES 30.9
SD 11.2

WIN41 3.66gr 31.8 SB6.5 85.5
10 shots
min 3031.3
avg 3061.0
max 3082.1
ES 50.8
SD 16.7

I have 10 more of each loaded the same night but will load some with about 1.5grains less powder.
Velocities were on the high side. That will give her 10 WIN41 with 31.8gr, 10 with 31.65gr, 10 CCI450 with the 31.8gr load and 10 with 31.65gr.
Plus a few foulers.

 

[MarkyMark007]

thx for the test.
like all testers see; primer weight IS corelated to velocity. no doubt.
it's just cartridge choice, if this is more or less visible.
with your choice of bad little cartridge: 22Nosler; and Staball powder (and maybe AR rifle), every variable is bigger than in bigger and more efficient cartridges.
so in your case, sorting (this LOT of) primers have big influence in velocity spread.

 

[secondofangle2]

Fools errand

 

[kthomas]

All good suggestions from everybody.
Was up late last night and thought of this.
Primer Orientation might make a difference.
View attachment 8380829

The Primer Weight test is open for anyone else to duplicate.
I'm just gonna shoot the already sorted bins to finish up this brick.

What is the datum point for which you are orienting the primer position off of?

 

[Threadcutter308]

I know people search for the perfect powder, charge weight, seating depth, neck tension maybe even primer brand, but wouldn't it be cool if something like this exists?

View attachment 8380801

To get this out of the way first; I have watched this thread, admittedly, not with a great deal of interest or enthusiasm. That's no slam or criticism on you (the OP) or anyone else you're interacting with. I just don't ever see myself even entering this rabbit hole, much less going down it. But feel free to knock yourself out and I hope you have fun and find satisfaction in doing so.

Having said that, is the above graph representative of "real world test results" ? Or, is it merely a model (with made up numbers) that have no correlation to real world test results ?

Glancing at it and using rough numbers, I take it to mean that it is saying that the velocity variation is about 80 FPS (3,060 FPS - 2980 FPS = 80 FPS) and the total primer weight variation is .2 Grains (3.8 Grains - 3.6 Grains = .2 Grains).

When it must be taken into consideration that the majority of the total primer weight is in the cup and anvil, that means that the priming compound represents a very small percentage of the total primer weight. So, a very small percentage of priming compound weight appears to have a not so insignificant effect on velocity.

Again, not slamming anyone, criticizing or calling anyone a liar, I just have a hard time buying in to what is being represented in the graph above. At least in terms of the magnitude of the variation(s) being represented.

I suppose your comment of "but wouldn't it be cool if something like this exists ?" tends to imply that it is not representative of real world testing results and that it is a model using made up numbers.

Please clarify.

Thank you.

 

[CK1.0]

Generally, I find threads like these more eye-rolling than eye-opening, but Interesting indeed. Bravo.

As usual, more/less fuel = more/less speed.

 

[Ex E6]

Primer mixture variation is but a small factor in the overall scheme of powder ignition . Known as " Brisance aka " shattering effect of a high explosive " . Again a misnomer as there's actually NO explosion but rather a controlled rate of burn quicker than powder.

All You ticklers load identical cartridge charge weights with weight matched bullets . Run #3 of X primer and #3 of XX primer and #3 of XXX primer ,same day shoot run all by your Chrony of choice . Report back to us for velocity gain or loss .

Magnum primers mixture is altered * for better Cold weather ignition , highly doubtful any alteration in actual weight but MORE Brisance , which actually is a HEAT value when referencing Primer ignition . Intensity duration varies tremendously . * Not all manufacturers change primer formulas !.
So they're simply Hood winking marketing BS . Those that do put in enough mixture to do either job ,yet charge more $'s for the illusion of magnum .

Borrowed This ,so evaluate or speculate at accuracy disclaimer : I will say this from experience , RWS primers will IGNITE WET POWDER !. Never had any 8mm or 9.73 x 74R fail and years ago one could order RWS most anything . In other words I've reloaded with them and you do need to adjust powder charges slightly ,to stay within recommended pressure margins .

https://www.6mmbr.com/primerpix.html

RIfle Primers
Brand/type_________Power Average___Range____Std. Dev
1... Fed Match GM215M___6.12______ 5.23-6.8_____.351
2... Federal 215 LRM _____5.69______ 5.2-6.5 _____.4437
3... CCI 250 LRM_________5.66______ 4.5-7.4_____ .4832
4... Winchester WLRM____ 5.45______ 5.1-6.0 _____.2046
5... Remington 9 1/2M LR _ 5.09 _____ 3.5-6.75 ____.6641
6... Winchester WLR _____ 4.8 ______ 4.1-6.0 _____.4300
7... Remington 9 1/2 LR __ 4.75 _____ 3.7-6.25 ____.5679
8... Fed Match GM210M __ 4.64 _____4.0-5.6 ____ .3296
9... Federal 210 LR ______ 4.62_____ 3.7-5.5 ____.3997
10.. CCI BR2 ____________4.37_____ 4.0-5.0 ____ .2460
11.. CCI 200 LR __________4.28 ____ 3.8-4.8 ____ .3218
12.. KVB 7 LR Russian_____ 4.27 ____3.8-4.8 ____ .2213
13.. Rem 91/2 (30 yrs old)_ 4.16 ____ 3.8-4.8 ____.3427

Pistol Primers
14 Rem LP ___________4.47_______ 3.2-5.6 _______.5171
15 KVB 45 LP Russian __3.89 _______3.3-4.2 _______ .2232
16 CCI 300 LP________ 3.18_______ 2.7-3.5 _______ .2406
17 Federal 150 LP _____3.11 _______2.6-3.5 _______.2090
18 Fed Match GM150M_ 3.05 _______ 2.6-3.7 ______ .2299

 

[Rocketvapor]

Yes, the modified graph is a guess, that turned out wrong
I reduced the powder charge for mine (AR)
and tried a small range of charge for the wife's Bolt gun.
Got an unexpected drop in velocity with the 31.65gr charge from the 31.8gr charge.
Here are the numbers, no graphs.

Added medium primer (3.66gr) 10 shots to above image that were mingled in with the blue ones (test 2).
Maybe I can find a few primers in the 3.710 to 3.715 range and load with 31.8gr for a later trip.

 

[Rocketvapor]

I'm done with Heavy/Light testing but will continue to sort, especially for matches.
As far as losing crud from the primers, probably very little is lost. I see no clumps of crud coming out of the primers. I very carefully remove them, weigh them, and put them in the flat in order shot.

Popped a few out.
First one of string 1, the really slow shot, started out as 0.2396g, ended up 0.2194g, for a loss of 0.0202g (0.3117gr)
Garmin velocity was 2910.3fps. Something other than primer compound going on with this one.
The first one from string 2 started out as 0.2394g, ended up 0.2198g, for a loss of 0.0196g (0.3025gr)
Garmin velocity was 2952.5fps
The first one from string 3, started out at 0.2398g , ended up 0.2200g for loss of 0.0198g (0.3056gr).
Garmin velocity was 2955.4fps, First one from string 3 shot yesterday (post #69).
The other outlier, shot 4 from string 2, started out as 0.2398g, ended up 0.2198g, for a loss of 0.0200g (0.3086gr).
Garmin velocity was 2929.7fps.

The average weight loss of the 15 heavy from previous test was 0.3597 grains,
The average weight loss of the 15 light from the previous test was 0.2617 grains.
Looks like the loss in this test of 30 medium (3.70gr) will be closer to 0.3070 grains.
Will post weight loss vs velocity results for all 30 when I get around to popping the rest out.

The heavy/light test was with a charge weight of 31.8gr of SB6.5,
this last test was with a lighter charge of 31.65gr of SB6.5.
Velocities were lower, of course, but the mid weight primers also had mid weight losses.
Go figure.

 

[Threadcutter308]

Yes, the modified graph is a guess, that turned out wrong
I reduced the powder charge for mine (AR)
and tried a small range of charge for the wife's Bolt gun.
Got an unexpected drop in velocity with the 31.65gr charge from the 31.8gr charge.
Here are the numbers, no graphs.
View attachment 8384352

Hmmmm, After looking at it/thinking about it, I could see where the basic concept is valid. What I would argue would be the magnitude of the velocity spread. I wouldn't be surprised to find out that there may actually be some velocity variation based on primer weight, but maybe only 10% of what was shown.

If indeed that is true, I would think it would be more obvious in smaller calibers/lower powder charges. As you go up in caliber/charge weight, I would think the velocity variation(s) would be a smaller and smaller percentage, compared to (increasing) case charge weight and get lost in the noise at some point.

I'm not trying to talk anyone into or out of anything. It's just that I believe I have already hit the point of diminishing returns with everything I am already doing and that sorting by primer weight isn't going to provide any additional benefit to me.

But you seem to be having fun doing it, so by all means, rock on

 

[RagnarAW50]

Rockvapor,

Great data! I shoot 50BMG 1000yd FCSA matches which are basically bench-rest, with the RWS primers we import we see differences in weight and we do know it affects SD to some degree....your data makes me feel better about sorting 3000 primers to .01 grains....great wintertime project...sort of... Thanks for posting!!!

 

[MarkyMark007]

rocketvapor; like I said: you have bad cartridge with bad powder.

I read old topics about weighting primers, and people usualy get 10-15fps / 0.1gr primer differnce. some are getting like 30fps/0,1gr difference, but your results are even higher at 50fps/0,1gr. imho this is very big.

so you will benefit from better cartridge and better powder.

 

[MarkyMark007]

dont get me wrong: I will sort my primers too, and see the results and I believe that this is good thing for the best result.
but your results are just too big, and if you compete in F-OPEN class, your cartridge-powder combo is just bad for good shooting.

 

[Bmghunter]

rocketvapor; like I said: you have bad cartridge with bad powder.

I read old topics about weighting primers, and people usualy get 10-15fps / 0.1gr primer differnce. some are getting like 30fps/0,1gr difference, but your results are even higher at 50fps/0,1gr. imho this is very big.

so you will benefit from better cartridge and better powder.

Would the fps/.1 gr primer weight be dependent on cartridge and bullet weight? His is a 22 nosler with a 80ish weight bullet. Seems to be on the smaller end of cartridge and bullet weights which might make the fps difference higher. Doing the same primer test on a 6.5 creed with 140 grain bullets, maybe the fps difference will be in the teens?

 

[RagnarAW50]

I think relative primer weight difference vs cartridge weight/size would be a factor. For 50BMG we did not test the relative affects, we just noticed the SDs were higher with unsorted primers...so I think we went from around single digits SDs sorted to 20-40 unsorted but I am not certain. For FCSA bench-rest style shooting I think it is worthwhile to do the sort, though it is not fun.... These are RWS 50BMG primers, with relatively large charges (240gr) and bullet weights (795gr).

 

[Rocketvapor]

I like my cartridge
Yes, for competition it puts us in F-Open and it will never be competitive against the 6.5's and 7's.
It' low recoil, and FASTER than .223.
The wife and I enjoy shooting and getting better.
We plan on moving up to 1000yds after we Master 600.
She has enough to move up I think. Got her first ever 200 this past Saturday

I can see the resistance to sorting primers for larger cartridges.
Probably very little impact for a tenth of a grain.
How about sorting for .223/5.56?

I'm into a new brick of primers. Who knows, I may end up with enough outliers to do another test.
can't let them go to waste

 

[RegionRat]

She has enough to move up I think. Got her first ever 200 this past Saturday

Congrats to her! Well Done!

 

[MarkyMark007]

I like my cartridge

Yes, I know that feel. That's why I stick to 223REM for F-TR.

I sorted Murom SRM primers for low, middle and high weight and I have a plan to test them at 1000m for vertical difference. I weight them with beam scale, so I don't know their exact weight but I only separate them in 3 different weight classes: low, middle and high.

Maybe I will post results here. But probably I won't measure muzzle velocity, because I'm selling my Labradar, I will only have targets and velocities from ShotMarker.

 

[Rocketvapor]

Even with a beam scale, sorting low, med, and high you should still be able to detect extreme outliers in weight.
Getting those few out of your competition load might help.

Now, back to the wife's bolt gun results.
I have to be real careful making comments that might embarrass her during a match but on her third string she had a run on 10's and asked her to STOP and evaluate her string.

She adjusted vertical, shot a few, adjusted up some more and shot the rest.
Would have blown the 200. Even then almost had a couple windage 9's.

 

[JerkyFreak]

Yeah, what she did after the first 2 shots is criminal. No wonder the x count is so low...

 

[Rocketvapor]

Yeah, after I went to all that trouble to sort her primers
She's still a little tense at prone competitions.
Third match after moving from an AR to the Bolt gun.
Saturday was an improvement from 97.5% to 98.7%.
Still out shot me though.

 

[Rocketvapor]

Did a abbreviated ladder Saturday @ 600yds.
Wife and her Savage 22Nosler, 95 SMK, SB6.5 and CCI450.
30.7gr is right at 100% fill seated about 15 off.
Now to fine tune the charge.
Normally shoot 85.5s @ about 2990fps.
The 95 might be better when she moves to 1000yd.

 

[MarkyMark007]

nice. I am using Sierra 95gr in 223REM too.

are you thinking about going to better extruded powder or you are happy with StaBall 6.5 performance?

 

[Rocketvapor]

I don't think we have squeezed all we can out of the SB 6.5.
The 22 Nosler gets really low speeds (per reloading data) with many of the popular powders.
I know speed isn't final goal but until we get better I'll stay with it.
I get anal with charge weight, finger trickling to +/- one count that turns out to be about +/- one little granule.