Weight sorting primers-Test

[Bart B.]

Sorry for the duplication Bart, your post appeared as I was typing!

No problem, thanks.

By the way, I've still got a 1000 round brown box of those original greasy, unpolished "standards" we used then, lot 1123-214.

 

[gilmillan1]

I am interested in seeing if there is a difference in group sizes between the heavies and the lightest primer. I would do three, three shot groups with the lightest and three, three shot groups with the heaviest. I would like to see if they change. i would also track the velocities with a decent chronograph. I think this is the real test.

 

[mikeeg02]

I am interested in seeing if there is a difference in group sizes between the heavies and the lightest primer. I would do three, three shot groups with the lightest and three, three shot groups with the heaviest. I would like to see if they change. i would also track the velocities with a decent chronograph. I think this is the real test.

This thread has a lot of testing and information on it as well. Lots of discussion, then his results start on page 7.

http://forum.accurateshooter.com/th...-spread-is-acceptable-in-competition.3960990/

EDIT: added quote

 

[Dave Way]

According to Federal, the only potential difference is that senior and presumably more experienced individuals assemble the match primers on certain days using the exact same components that go into the non-match versions. In fact, that might not even be a difference if your primers were assembled by any of those individuals on a day they weren't making "match" primers.

Twp416's results are interesting, thanks very much for posting them. The priming compound looks to make up less than 10% of the total weight of an assembled primer. Although the primer total weights didn't differ by what I would consider a HUGE amount, nonetheless there was variance. The weight of the cups/anvils appeared to be very uniform in this sample set, not totally shocking for stamped metal parts. However, because the priming compound makes up less than 10% of the total unfired primer weight, that means the metal parts make up better than 90% of the total weight. In fact, the priming compound probably makes up even less of the total because the ash residue, which doesn't leave the cup or directly contribute toward combustion, was removed. So even small variance in the weight of the cup/anvil could potentially have a large impact on overall primer weight for the purpose of sorting.

The only suggestions I would make are that it would be preferable to use a balance capable of resolving to 0.1 mg. The milligram balance apparently worked ok for this part of the test, but ultimately, if velocity comparisons are also carried out using different weight primer sets, the extra digit might make a difference in the final values +/- SD. I have weighed a box of Fed205s and found only a 6 mg difference across all 100 primers (i.e. median +/- 3 mg). Finally, it would be interesting to weight the primers after firing, but before cleaning to determine on a weight basis how much (ash) residue actually remains in the primer and therefore does not contribute to powder ignition. The amount of priming compound that actually contributes to powder ignition may even be a much smaller fraction of the total primer weight.

I'll be very interested to see if you do anything more with this in terms of velocity testing. Thanks again for sharing your results!

Actually I did weigh the fired primers before disassembling and cleaning them. Each ended up having the same amount of ash, 0.002g. I didn’t include that number in the opening post to keep things simple. Thanks-Dave.

 

[Bart B.]

He turned out some fine ammo, and while the Ruger rifles were a colossal flop, I don’t recall hearing a single negative word about the issued ammo.

In the June, 1991 Rocky Mtn. Palma Matches when the '92 Palma ammo was first used, people using barrels shorter than 28" reported occasional loss of accuracy at 900 and 1000 yards.

The consensus was those barrels were too short to shoot the 155's fast enough to stay supersonic at the longer ranges.

 

[dcali]

A Federal rep told me their 210M primers are made the same as regular 210 ones. Their difference is their flame output uniformity. Some batches get their mix more uniform as well as how uniform the wet slurry gets spread in the pellet cups to dry. He said the process was oft times called black magic.

He described the mixing process as much like mixing chocolate on a granite slab with straight edge paddles. Some people have the knack and techniques to do it better. This was back in the 1980's and I dont know if machines mix the slurry now.

Good technical info on primers, search for "a114616.pdf"

The cynic in me says that this sounds a whole lot like "an extra few bucks a box".

 

[centershot]

Bart, do you recall how the ammo was loaded? Sierra bullets, but what powder, amount, cases and primers? I shot 185s at 1000 and was able to keep them supersonic in a .308 with H4895. Believe the barrel was 26". Was about 90*. Very interesting topic! BTW, does Bob still live in Phoenix?

 

[Ned Ludd]

Actually I did weigh the fired primers before disassembling and cleaning them. Each ended up having the same amount of ash, 0.002g. I didn’t include that number in the opening post to keep things simple. Thanks-Dave.

Thanks, good to know.

 

[Bart B.]

Bart, do you recall how the ammo was loaded? Sierra bullets, but what powder, amount, cases and primers? I shot 185s at 1000 and was able to keep them supersonic in a .308 with H4895. Believe the barrel was 26". Was about 90*. Very interesting topic! BTW, does Bob still live in Phoenix?

Two Dillon 1050 progressives, one uniformed necks in new Winchester cases and seated 210M primers, next 1050 metered 45.3 grains of IMR4895 (0.3 grain spread) then seated 155's to about 2.85" OAL (.0035" max runout). 20 shots tested 2.7" at 600 in Jensen's Palma rifle.

Imr4064 was popular with 168 to 190 grain bullets in 308 cases. Imr4350 with 200's.

I think Bob passed a few years ago.

 

[SAP]

So there is a 16% weight difference in the priming compound. Sounds like a lot.
The $64,000,000 question is does it show up on the target?

Just my two sense but last year I decided not to weigh and sort primers and concentrate on other areas. I shot better than I ever did.

 

[centershot]

Two Dillon 1050 progressives, one uniformed necks in new Winchester cases and seated 210M primers, next 1050 metered 45.3 grains of IMR4895 (0.3 grain spread) then seated 155's to about 2.85" OAL (.0035" max runout). 20 shots tested 2.7" at 600 in Jensen's Palma rifle.

Imr4064 was popular with 168 to 190 grain bullets in 308 cases. Imr4350 with 200's.

I think Bob passed a few years ago.

I bought a lot of guns from him when I was stationed in Tucson.

 

[Puzzaz01]

This is the link to the primer flash photo test from the 6BR.com site. http://www.6mmbr.com/primerpix.html
It's really worth a look.

Darrin

 

[JimSC]

I believe the main question is would a 16% change weight affect the brisance to a noticeable degree? Related questions might be.

Changing the brand of primer can have noticeable effects on SD and different primers have different brisances. That's been proven over and over but how much would a 16% change in weight affect the brisance ? Would it be enough to reflect on paper at 100 or 1000 yards ? Would a 16% difference in brand A have the same effect as a 16% difference in brand B ? Would the effect on powder A be the same as the effect using powder B ? How far into the weeds do you want to go ?

 

[Dusty Stevens]

I believe the main question is would a 16% change weight affect the brisance to a noticeable degree? Related questions might be.

Changing the brand of primer can have noticeable effects on SD and different primers have different brisances. That's been proven over and over but how much would a 16% change in weight affect the brisance ? Would it be enough to reflect on paper at 100 or 1000 yards ? Would a 16% difference in brand A have the same effect as a 16% difference in brand B ? Would the effect on powder A be the same as the effect using powder B ? How far into the weeds do you want to go ?

We need someone like @dmoran to do a test. He is good with data and can shoot good enough to see a difference

 

[dmoran]

@Dusty Stevens
Problem is, primer results are an evolving aspect.
Even from the same brand+type primers with the same rifle-n-load, just a lot change can change the results.
I've had primer lots that I could see no noticeable difference, and other lots that yielded obvious differences.

Plain and simply, from my own testing experience: primers are an ongoing and evolving component aspect, that will always need individual testing to each ones own scenario's and components used, to every brand, type, and lot.

 

[savagedasher]

Doesn’t everyone check the primers
For standard deviations
I have found 18 “ difference
That is the first test I do

 

[butchlambert]

Geezzz, It must be winter time. About the Federal primers, the only difference between the regular and match primers is a visual. The best primers in the World would not win a match for me or most anybody.
I think any testing would need to be done with an unlimited rifle in a tunnel.

 

[Dusty Stevens]

Geezzz, It must be winter time. About the Federal primers, the only difference between the regular and match primers is a visual. The best primers in the World would not win a match for me or most anybody.
I think any testing would need to be done with an unlimited rifle in a tunnel.

Thats what the federal guys told me at a match one time but nobody believes me

 

[butchlambert]

Thats what the federal guys told me at a match one time but nobody believes me

Ain't a secret Dusty, it is the gospel.

 

[Dusty Stevens]

Ain't a secret Dusty, it is the gospel.

Everytime i bring it up it gets shot down