Rifle primer consistency , which would you prefer ?

[Metal god]

The over all question is if you're not using BR/match primers and your primers were inconsistent . Which type of primer would you want . The very high flash almost magnum flash type primers or the lower flash almost match type flash primers ?

I've been giving this some thought lately after trying some different primers in 308 ( Large rifle CCI , Win & Fed 210m ) I bought a brick of the Fed match primers a couple years ago in hopes of really making that uber consistent load after always using Win primers . After multiple load developments I have not found them to be any better then Win primers as far as finding a nice group or ES/SD .

Now I've only loaded about 350 of the Fed match primers but they have all been for load development and my loads don't seem to be any more consistent or group any better . FWIW this is using IMR 4064/4895 , AR-comp with 175gr SMK & TMK as well as 168gr BTHP ( Hornady ) so there are other quality components involved with these loads .

I should add that I'm not loading for a bench rest rifle or anything custom . These are commercial rifles such as Savage model 10 or Ruger PR type quality . This means I can't shoot little tiny bug holes but can consistently do half moa when I try .

So back to the original point , I have to assume you can only get the powder burning so good . The more flash you have at some point does not benefit anything assuming you are using a powder that burns well .

My thinking is if you're going to have any inconsistencies with your primers . I'd think you'd want to use a very high flash primer . Which to me would mean even if a primer had a little less energy then the rest it would still ignite the powder quite well and comparatively consistently . Rather then having a primer that had a lower average flash but at times would have a bigger or even lower flash then it's average do to inconsistencies resulting is the powder burn being inconsistent ???

Which inconsistent type primer would give you the most consistency ? err wait what ?

[cdoc42]

For 40 years I've used CCI standard and magnum primers in small and large pistol, standard and large rifle. On one occasion when primers were harder to find, I ran into Remington small rifle 7-1/2 and I found they gave me smaller groups in my 6mm PPC.
In one of those reloader experimentation fits I get more than I should, I bought Winchester small rifle primers (just in case I can't get anything else) but I have yet to try them.

I happened across Fed 210 and Fed 215 primers which also seemed to give me better goups in my .270 and 7mm Rem Mag. Looking for more 215's, but the dealer was out of them but had 215 Match, so I thought, how much better can you get? So far I'm disappointed - no consistent difference compared to CCI, at least in my .270 and 7mm RM.

After all is said and done I'm becoming convinced that I concentrate better if I think a new primer should give me better groups, and therefore it does. On other days when that is not my mode driver, I get groups just as good with the CCIs. Except with the PPC.

[Slamfire]

I've been giving this some thought lately after trying some different primers in 308 ( Large rifle CCI , Win & Fed 210m ) I bought a brick of the Fed match primers a couple years ago in hopes of really making that uber consistent load after always using Win primers . After multiple load developments I have not found them to be any better then Win primers as far as finding a nice group or ES/SD .

The effect due to primers is very subtle. I have friends who are F Class National Champions, they extensively experiment, and whatever combination shoots best, they use that. While CCI Benchrest primers are very common, they are not used exclusively. In fact, the Russian primers (TULA) have an excellent reputation.

A bud of mine worked Calibration/Gaging for a Government Agency and visited Army Ammunition Plants. He stated out of the guys making primer mix, the guy who made the most consistent primer mix was given a bonus, but, no one monopolized the bonus money. Bud also stated that the instrumented "mules" used in primer testing measured everything, such as the amount of matter ejected, temperatures, flames, flame time, etc, etc, etc.

The next lot of primers you buy will be different from the last lot.

The current military primer mix is the FA 956 mix,

PATR 2700 Encyclopedia of Explosives Vol 8 gives the composition

FA 956

Lead Styphanate 37.7 +/- 5%
Tetracene 4.0 +/- 1%
Barium Nitrate 32.0 +/- 5%
Antimony Sulfide 15.0 +/- 2%
Aluminum Powder 7.0 +/- 1%
PETN 5.0 +/- 1%
Gum Arabic 0.2%

As can be seen, there are tolerances for the composition within the mix. Also, purity of the constituents will be different batch to batch. Therefore you can expect a variance with the flame and flame intensity lot to lot.

I use standard primers in my standard cases and I have used standard primers in my 300 H&H and it held the ten ring out to three hundred yards, the limit of my testing with that round. Very big cartridges seem to require magnum primers. CCI #34 primers are claimed to be magnum level but I have not seen any velocity difference over the screens. I do know that ball powders are harder to ignite, which is why the "military" primers are supposed to be magnum primers as the military wants their guns to go bang in the cold.

It is hard to over estimate the influence of advertising on behaviors within the shooting community. Manufacturer's stamp "Match" or "Sniper", or "Extreme" on something and the shooting community goes nuts over the product. You will read fanatical claims about someone's Extreme Sniper Match primer or bullet giving sub MOA groups at thousands or yards.What these guys are in fact reporting is the result of Confirmation Bias. The shooter paid more, therefore expects more, reports what he remembers as more, but is in fact, ignoring the less. Anyone remember the Coke versus Pepsi taste tests?, it showed that people had strong behavioral preferences based on emotions not taste. http://web.bend.k12.or.us/jeremy.rub...20research.pdf

https://www.psychologytoday.com/blog...oke-over-pepsi

Federal Match primers were the most slamfiring primer in the history of NRA Highpower, and yet, it was the most popular primer because Federal stamped "Match" on the box. Federal also charged more. What we, the shooting community don't know, is how much better, or even if these premium primers were any better, than standard primers.

This is one reason Eley refuses to test Black Box rimfire ammunition in customer rifles at their test center. They will test Red Box, but you have to pay hundreds of dollars more for a case of Red Box over Black Box. Lapua stop testing Rifle Match in their test center, because once shooters saw objective evidence the the $1750 a case ammunition was slightly better, or maybe not better, than the $1500 a case, or even the $800.00 a case (Rifle match), shooters had the choice of buying the cheaper stuff.

As Orwell wrote in the book "1984", Ignorance is strength. Ignorance of the masses is the strength of the elites.

So, my opinion. load your ammunition and go shoot. If you like the group, the bullet is good, the powder is good, the case is good, and the primer is good.

[emcon5]

Now I've only loaded about 350 of the Fed match primers but they have all been for load development and my loads don't seem to be any more consistent or group any better . FWIW this is using IMR 4064/4895 , AR-comp with 175gr SMK & TMK as well as 168gr BTHP ( Hornady ) so there are other quality components involved with these loads .

There is no difference between the standard Federal primers and the Gold Medal Match equivalent as far as compound goes, the GMM are just held to higher standards of QC.

I contacted Federal a while back on this subject when GMM was impossible to find, and was trying to determine if I could substitute the standard Federal primers without having to work up a new load, they confirmed they were completely interchangeable.

For precision stuff I only use match primers, I honestly don't know if they make a noticeable difference, but for the price difference, about 1/2¢ each for Federal, (I think Remington SRBR primers are actually the same price as standard), it is cheap insurance. Precision reloading is all about minimizing variables, and using Match over standard primers is kind of a no-brainer in that regard.

[OzeanJaeger]

I was told, buy a guy who manages one of the large reloading houses, that when he toured the CCI plant they showed him the difference between a BR primer and a regular one... An additional visual check. They come off the same machine and are made the same way, but a tech looks them over an additional time...

Believe it or not, and take it for what it's worth. The BR primers are only a couple of bucks more per 1000, so if it makes you feel better use them, but I believe the guy.

[RC20]

Not in our neck of the woods. CCI 200 are a good $20 less a box.

I got some BR2 on sale, no difference that I could tell but then I am still learning how to shoot!

[444]

Part of this hobby that I really enjoy is reloading. I try to produce the most consistent ammunition I can: regardless of what I am shooting it out of and regardless of what distance I am shooting it at.

So, at some point during load development I play around with primers. I mainly look at the SD and choose whatever primer gives me the lowest SD. And there isn't one single brand or type of primer that gives me the lowest SD in every rifle I load and every caliber I load for.

The only way to decide is to test them and see what you get.

I personally have never found "benchrest" primers to shoot any better than anything else.

[Metal god]

Here is what I was saying about flash size and the differences from brand to brand
http://www.6mmbr.com/primerpix.html

My thinking is that you'd want the higher flash primers "if" there were to be inconsistencies ????? That way the powder would be ignited pretty much the same even if there was a little less flash because you only need so much to get the powder going .

Am I on the wrong train of thought to think those really small flash could cause more inconsistencies the high flash primers , especially with ball powders in large cartridges ???

On a side note and to Slamfire's point of magnum primers with ball powders . IMO magnum primers should not be needed in smaller cases like the 223/5.56 . There's really not that much powder that needs to be ignited . I've done some limited test that actually showed magnum primers were much more inconsistent in the 223 when it came to avg velocity and ES/SD then standard primers .

Hmm it seems my last two points are at odds with one another . Did I answer my own question ?

[Unclenick]

The flash brightness is mainly about the aluminum content. CCI went to it (or, more of it) in their magnum primers in 1989 because that aluminum spark shower seemed to improve ignition of the spherical powders then in use, as did the high temperature from using a barium oxidizer.

The only technical difference between magnum and standard primers is that the magnum primers make a larger volume of gas. This is to establish adequate start pressure in large cases. It also helps in a more medium size case when there is extra space due to low loading density.

Via phone calls, CCI has verified their 450 SR Magnum primer and their #41 military sensitivity primer have the same amount of the same priming mix. The only difference is in the anvil used to produces the lower military spec sensitivity in the #41. Same for their 250 and #34 primers. So the #41 and #34 have magnum priming mix in magnum quantities.

The trick with better ignition has to do with flame temperature, spark shower temperature, and duration as well as pressurization of the case. You are limited in how well you can tell a primer is doing that by looking at the flame photos. This is for the same reason that just because a candle makes brighter light than a propane torch flame, does not mean it is hotter or more energetic. It just means it puts more energy into the visible light spectrum and that's just a portion of the total energy of the reaction.

You can get a primer to make magnum levels of gas different ways. You can just increase the total priming mix or you can increase some of the fuel chemicals without increasing the amount of sensitizer and thus get more gas at lower brissance and with lower peak temperature but with longer flame duration. What strategy works best is powder dependent. QuickLOAD's author, Hartmut Broemel, points out that going to a magnum primer occasionally actually lowers muzzle velocity. This is because of the variety of approaches to making the primer produce more gas.

What you want to look at in primer reviews are the muzzle velocities achieved (higher means the powder got burning faster due either to more or better tuned (for temperature and duration) primer energy), and muzzle velocity SD's with your powder. If your powder isn't listed, you need to test it for yourself. For a given primer, some powders produce the best accuracy (at least, at closer ranges) without producing the lowest MV SD's. But I don't believe I've ever seen an example of a primer that produced the lowest MV SD's with a particular powder not also producing the smallest groups with it once the charge weight and bullet seating depth were tweaked to a sweet spot while using that primer. So look at MV SD as an indicator of consistent ignition (smaller is better) when comparing primers in your gun.