Primers - Let's Get Real!

[JohndeFresno]

"If you change any component of a load, you should start over by reducing your load by 10% and working back up to your load." Implied or stated literally - "this includes primers." So says every reloading manual, article, and website that I have come across. But I have not noticed a perceptible change in loads that use different primers OF THE SAME TYPE.

Then again, I am talking about fairly pedestrian loads; because I stay with every component and carefully work up to the hotter loads, and don't try to keep up with some the the hotter handloaders like John Taffin. I say this so that we can stay on the issue and avoid all of the posts stating the well known provisos of not mixing primer types without starting over, that hot loads need special care and caution, etc. etc.

So here is the question - has anybody clocked loads for comparison, using different but SAME TYPE primers, where all the other components are the same? In other words, truly compatible primers like these Large Rifle Primers:
CCI 200
Fed 210
Rem 9 1/2
Win WLR
But NOT Bench Rest or Magnum LR Primers like CCI BR2, FED 215, Rem 91/2M, and Win WLRM.

I frequently hear, for instance, that Federal primers are hotter and more easily ignited. That might indicate that these would indeed affect pressures during ignition. But I'm from Missouri - well, my dear ol' Dad was. I need to actually see the data before I believe these vague but relevant statements.

If you have done any direct comparisons, how 'bout educatin' us?

[Lefty Dude]

I have clocked shotgun loads with different primers, got a 200fps difference.

[arjunky]

Winchester rifle primers I believe are considered a magnum primer anymore. They don't have 2 kinds anymore.
Other than that I don't think you will have any problems.
There was an article a few years ago testing all available primers with the same load. Pressure, velocity and SD were all listed.
If I remember right it wasn't always the magnum primer with the higher velocities.
Pretty sure the Federal Magnum primers were always the hottest though.

Byron

[Terry Murbach]

I HAVE RUN THOUSANDS OF ROUNDS THROUGH A PRESSURE GUN TESTING LOADS WITH DIFFERENT PRIMERS AND THE CHANGES CAN BE STARTLING TO THE POINT OF INCREDULITY.
IF YOUR TRYING TO CONVINCE YOURSELF THAT YOUR LOAD DEVELOPEMENT FOR YOUR GUNS IS A WASTE OF TIME YOU ARE BARKING UP THE WRONG TREE. YOU CANNOT CHANGE THINGS WILLY NILLY WITHOUT PAYING THE PIPER SOONER OR LATER. SOME TIMES THAT PIPER'S BILL IS AN EXPENSIVE ESSOBEE TOO !!!
I START ALL OVER WITH LOAD DEVELOPEMENT FOR ANY CARTRIDGE WHENEVER I CHANGE EVEN THE PRODUCTION LOT OF PRIMERS.
I KNOW OF ONE PROPELLENT THAT CAN GO FROM STANDARD PRESSURE TO PROOF LOAD PRESSURES WITH A PARTICULAR CHANGE OF PRIMERS.
AND SO IT GOES...
OH...AND NEVER FORGET THERE ARE NO FREE LUNCHES FOR ANYONE ANYTIME ANY WHERE NO HOW NO WAY.

[Borregos]

Terry, you are SOOOOOOOO RIGHT

[JohndeFresno]

Wow. Thanks for the wake-up call, guys.

I purchased a chronograph a couple of years ago, but just started using it last year. As such, I have just started actually clocking my various loads with careful specifity; having previously used "safe" load workups while looking for signs of pressure, etc.

After researching this "signs of pressure" stuff rather thoroughly and reading about so many instances where the early warning pressure signs are too subtle for many if not most to discern, I decided to start us of my chronograph exclusively, even though it involves packing the extra equipment and setting it up properly, ten feet in front of the firing line.

So far, my tests of the QuickLoad software, which does not take into account the type of primer used, have shown remarkably close estimates to what my chronograph shows; but I'll accept what Mr. Murdoch says, and not bet against that time when things go wrong.

Again, thanks for the input; I'll take primer selection a lot more seriously, now.

[Rimfire McNutjob]

I have to give credit for this link to Tycer. It shows the varying energy from the same type of primers of different brands. I think it backs up Terry's statement well.

[Sixgun]

I too, have run tens of thousands of loads through regular guns, testing primers and loads using only a chronograph. My testing was no where near as scientific or accurate as Terry's and to be truthful, I never could tell much of a difference between brands of primers (L.R.-L.R.........S.P.-S-P., etc) But..............98% of my loads are with cast bullets in the 18,000-28,000 test range. Remington always tested as the mildest with Winchester as the hottest-----remember now--not much within my pressure range.

Its another whole world when dealing with 55-60000 range. Thats when I would take Terry's advice as once again, to be truthful, Terry has forgotten more than most of us will ever know.-------------------Sixgun

[JohndeFresno]

Thanks, McNJ - pdf'd and archived. Dramatic differences.

[JohndeFresno]

I too, have run tens of thousands of loads through regular guns, testing primers and loads using only a chronograph. My testing was no where near as scientific or accurate as Terry's and to be truthful, I never could tell much of a difference between brands of primers (L.R.-L.R.........S.P.-S-P., etc) But..............98% of my loads are with cast bullets in the 18,000-28,000 test range. Remington always tested as the mildest with Winchester as the hottest-----remember now--not much within my pressure range.

Its another whole world when dealing with 55-60000 range. Thats when I would take Terry's advice as once again, to be truthful, Terry has forgotten more than most of us will ever know.-------------------Sixgun

Sixgun, that might be why I didn't seem to be able to tell the difference. Most of my loads have been pretty mild for target practice and plinking, and they all seemed to group about the same, extract the same, look the same, and so on. For hunting, I had previously just used factory ammo after sighting it in.

But now this is quite an issue, since: 1) I'm stocking up on serious handloaded ammo for a day when there won't be any sold, perhaps; 2) The newly mandated all copper loads are very expensive, especially when one has several calibers to feed; so I have started loading my own Barnes hunting loads at higher pressures than my other stuff. The bullets still cost around $.60 each (just the bullet) or more, depending upon the caliber!

I suspect that other handloaders will also read these posts and be warned to take those little firestarters a little more seriously.

[tdoor]

About 20 years ago I experimented with identical components, the only variable being the primer. The load (from a Hornady manual) was a grain or two below listed maximum for W760, Hornady 120 gr bullet in 257 Roberts (and it was a lever gun -BLR 81 which I still have); I first developed the load with CCI 200 primers and used it as a hunting load (I forget the velocity) and it showed no obvious pressure signs. Using brass from the same lot, identically prepared, after hunting season I substituted Fed 210 primers. They chronographed almost 100 fps more, but had obvious pressure signs, including a couple of leaky primers.

Usually, since I shoot mostly cast bullets and typically stay away from near max loads even with jacketed, I can't say I've ever seen such a dramatic difference, although I haven't used the chrony too much in the last 15 years or so.
tdoor

[KWK]

From what I've read, you can't safely gauge pressures with a chronograph. A while back, I assembled what data I'd seen into a web page. Basically, small changes in velocity can come with great increases in pressure.

[Don McDowell]

Do not EVER think a chronograph by itself can tell you ANYTHING but how fast the bullet is going. It takes equipment designed to take pressure readings to tell you at what pressure a load is operating at.
Take a look at something like one of the recent Lyman Reloading handbooks. You'll quickly see that just because a certain powder and bullet combination might be moving slowly doesn't mean that its not running on the ragged edge of upper pressure limits. Hogdons data with trailboss powder is an excellent example of how low velocity does not mean low pressures.

The old saw about always reworking the load when changing components is probably another of those stupid rules that was wrote by somebodies blood.
Change a primer rework the load.

[PaulB]

Well, I can see not reworking the load when going from heavier cases to lighter ones, for example. Hard to imagine pressure getting higher in that case. But primers? That's the last thing I'd take a short-cut with.

So far, my tests of the QuickLoad software, which does not take into account the type of primer used

Which, if the above comments are to be believed, basically makes QuickLoad worthless. Now that is something strange, now that I think of it. If I'm not mistaken, Mic McPherson is a big proponent of QuickLoad - yet I've seen warnings from him about substituting primers too.

[JohndeFresno]

I did not mean to mislead anybody about the use of a chronograph; I use it in * conjunction * with what I should be expecting from the load for each powder and bullet combination as listed in my various manuals - Accurate, Barnes, Hodgdon, Hornady, IMR , Lee (although that is imprecise), Lyman, Sierra, Speer, and one or two others; Handloader and other mags; and the loads listed in software like QuickLoad and RCBS Load. I've spent a small fortune in just amassing the library, given my resources. In fact, I purchased several of these books and read most of the articles in them for a full year before I loaded my first round. I tend to be a careful person. I would advise anybody pursuing this hobby to do the same.

And I believe every handloader should double check from a variety of sources.

However, your linked website article on primers and pressure is an eye opener, KWK; especially now that I plan to start loading for longer range hunting velocities rather then the rather mild handgun and medium .30-30 class loads that I have concentrated upon up until now. I hope the rest of us have clicked on the article. I plan to take that "5% less" solution to heart, for the warmer loads that I intended to load; and then continue to do my best to look for pressure signs, as vague as they might sometimes tend to be.

I'm certainly glad that I raised the subject of this thread; and although I've reloaded several thousand rounds of some dozen calibers over the past 6 years or so, I'm not too proud to admit that there is a ton of stuff here that I was not fully aware of. It's too bad that there doesn't appear to be a lot of knowledgeable handloaders in my city; but then again that's partly why I visit this website so regularly. Thanks again to all.

[Jaguarundi]

Terry, you are SOOOOOOOO RIGHT

+1 You nailed it ! Pay attention y'all !!!

[Mike Rintoul]

John: As an ammunition manufacturer I have access to information that is not generally available to the home handloader. Without getting into a lot of mumbo jumbo let me share a few things. Primers are rated on 1) Flame Duration 2) Flame Column, and 3) Flame peak temperature. Generally speaking, CCI offers the longest flame duration and longest flame column among all the brands of similar primers. When you say Federal primers are "known to be hot" that monicker probably came up because they are strong in one of the characteristics of primers. I'm not going to get into specs for individual brands for a number of reasons. However, primers can add from 3 - 13 psi pressure variance. Mag primers usually add closer to the 13 psi over the standard with the same load. What the variance in primers does is change the combustion rate and peak of your powder. Think of it in the most simple terms. Do NOT do this but for illustration think of this. You poured out a thin line of powders of different types that were the same length and width exactly. You touch a match to the very tip of each line and timed how long it took to get to the other side. The powder burn rate is the difference since the matches are the same and the starting ignition point is the same. Now, take the slowest powder and use a BIC type lighter on full blast. Touch the powder so that that BIC flame's entire length touches the powder line. That powder now has a head start over the one's lit by the match because you are lighting over an inch at once instead of just the tip like you did with the match. That line will burn to the other end much faster than it did when you lit the tip with a match. I hope this sloppy illustation gives you the idea. The flame column and flame duration greatly effect how much powder is burned while still in the case compared to how much is still burning as the bullet leaves the case. The burn temperature of the primer has less influence on the burning of the powder overall, but more effect on how quickly the powder actually ignites (with is microseconds obviously) with the external influence being atmospheric pressure and outside temperature. SO - primers do make a big difference. All of our loads are tailored to optimum performance with a certain primer. For your own load work-up you will find differences in accuracy and velocity by the simple switch of a primer. There are going to be some pressure differences too that you may not be able to detect at home but as usual, look for common signs of high pressure. GOOD LUCK!

Mike Rintoul
Grizzly Cartridge Ammunition Company
Rainier, Oregon
(503) 556-3006

[KWK]

However, primers can add from 3 - 13 psi pressure variance. Mag primers usually add closer to the 13 psi over the standard with the same load.

I assume you meant to type 13 ksi instead of 13 psi, or maybe 13%. Accuracy to 13 psi on a 63,000 psi reading would be incredible.

[JohndeFresno]

Excellent posts. Now I am really educated, and can appreciate the significance of redoing a load from the "bottom up", even with primer changes. And Mike, your analogy of the burning characteristics of a primer makes a lot of sense - it belongs in an ABC's of Reloading, somewhere. I'm archiving this thread with other valuable info that I plan to pass on to my Grandson.

[J Miller]

Mike, thanks for that well written bit of knowledge. As much as it explains, it also brings up more questions.

Well, I set up my hand loads with Winchester primers. I know how they work as I've used the same loads for many years. I guess I'll have to re-think some things when I do more loading now. But first I'm gonna buy me a big bottle of Excedrin cos thinking gives me a headache.

Joe

[MT Gianni]

Test your primers for accuracy as long as you are testing. Variance between make can be a big difference whether shooting PPC or hi-power. Gianni