Any difference in Primer brands ?

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This came up in a different thread and so I thought I would ask the question in its' own thread.

Anyone notice any difference in performance (etc) from brand to brand (of primers) ???

Rick Courtright

Mar 10, 2002
Redlands CA USA

My limited experience says it depends on what you're loading:

When loading shotshells, the rule has always been "Load it EXACTLY as the recipe's written," and, yes, I've seen differences between brands when testing otherwise "identical" loads.

When loading metallic cartridges, the word's always been to "Start low and work up," which is what I've always done whenever I changed any component from the published recipe (brand of brass, primer, powder lot, bullet.) By doing so, I've found a good load can be found w/ any of the primer brands I've tried. It seems metallic loading's at least a bit "forgiving" w/ respect to component changes (if not taken to excess.)

But I haven't done much "single variable" head to head testing w/ metallics as I've done w/ shotshells, so it would be foolish of me to say anything I've experienced should be carved in stone.

Remember, of course, that ol' YMMV thing... ;)

Rick C


Ruger Guru
Sep 18, 2002
Lake Lure NC USA
In general, as long as you stay with the same type, (small pistol for brand X & Y & Z) and stay within the safety guidelines, you'll most likely NOT see any differences worth noting.
However, that said, in rifles, there can be a bit more of a noticable difference, in groups sizes SOMETIMES. It all comes down to how much of a difference you expect. if I'm shooting a rifle, with components I've found to be very good, (say 1/2" groups at 100 yds,) and all I switch is the primer and my groups go to 5/8', then I'm only gonna worry if I'm shooting it in competition. But for general field use, I wouldn't care.
In handguns, most folks won't be able to tell any differences.

J Miller

Sep 30, 2000
Not in IL anymore ... :)
Yep there sure is differences between primers. Some are brass colored, some are silver colored and they come in different colored boxes ....... :twisted: :roll:

Seriously though I did an impromptu primer test a couple years ago. I loaded up a bunch of .45 Colt ammo using the four major brands of LP primers, same powder charge, same cases, and the same type and weight of bullets.
( Here we go, I found the link: ... W=J+Miller )

From the two .45 Colt revolvers I had on hand, at the indoor range I couldn't tell any difference at all.
They all produced good groups, and they all fired.

So unless your working up target loads, or special maxed out hunting loads, I wouldn't worry one bit about them.



Apr 10, 2005
Depends on what your requirements are.
I can prove on a target that there is an accuracy difference in one rifle primer over another. And the further-out you go, the more obvious that difference becomes. At 300 yds and beyound, the difference can be startling.:shock: .

On the other hand, I can't shoot a pistol good enough to detect a practical difference in any of them. So I have to go by what I see when I look at the primer itself....and how much (or how little) "stuff" is left behind in the bore.
That said, I do gots my own preferences.
When ya get down to the shooting-part though, it don't much matter what I think because my handgun(s) don't seem to care. I can shoot as badly with one primer one as the other. :lol: .

That's all I know about that.



Jun 18, 2008
I have seen spikes in pressure when changing primers.

Years ago I had worked up a max load in a S&W 686 revolver with Blue Dot and standard primers. Not thinking, I loaded up the same charge of powder, but substituted CCI 550 small mag pistol primers. The result was flattened primers and sticky case extraction. I had loaded 50. After that first cylinder, I went home and pulled the remaining 44 rounds and started over.

Another time I had loaded up some 45 auto rounds with 200 grain Speer bullets. A switch from Federal Magnum large pistol primers to CCI 350 magnum large pistol primers caused an increase in velocity of ~ 59 fps from a 4" 1911 as tested over my chrony.

Rex Driver

Oct 8, 2007
Colonial Heights, Va.
I do not claim to be an expert on this subject and can only tell you about my experiences. I shoot cowboy action and a bit of IDPA with a revolver and can tell you that there does seem to be a difference in hardness on the striking area of the primer. I shoot Vaqueros, GP 100s and a marlin 1894, all using pistol rounds and small pistol primers. I have found that Federal seem to be able to ignite with softer springs than the rest with CCI being the toughest. I also use some Winchester and Remington and feel them to be in between in hardness. This is a very amateur observation based on my guns which mostly have Wolf Springs of different weights. As far as difference between standard and mag primers in small pistol, I still go by my calculation that the mag will add about .2 grains of Win 231 to the velocity of my rounds.

Driftwood Johnson

Sep 25, 2007
Land of the Pilgrims

I agree with Rex Driver. A lot of us Cowboy shooters have our guns tuned up and that often includes light hammer springs. It is the general consensus in the CAS community that Federal primers are the easiest to ignite, Winchesters require a bit more of a smack, and CCI require the hardest firing pin impact of all. I have used both Federal and Winchesters interchangeably for years and cannot detect any difference, other than the ease of ignition. I have one Colt that does not always reliably ignite Federals, so I always load 45 Colt with Federal Large Pistol Primers. I also have a bunch of old S&W double action revolvers with light hammer springs, so I always use Federals for 38 Special and 44 Special too.


Aug 31, 2005
FOr hand held pistol, just buy the right ones and you'll be fine.



Aug 4, 2007
I found this post somewhere a few weeks ago. I cannot vouch for it, but see no reason why it would have false information. The info does back up similar info that I've heard before. Supposedly, the thinnest primer cup, the Federal, should ignite the easiest; very important if you have ignition problems with one of your guns. I have always used Winchester large pistol without problems, WLP's, and see no reason to change.

The important aspect of a primer in high-pressure loads is the cup thickness. The .454 Cassull generates pressures in the order of 60,000PSI which is right in the range of rifle pressures. A regular pistol primer would pierce or worse under these pressures.

I use a Remington 7 1/2 in my hot .223 loads, the cup thickness of this primer is .025 inch. This primer along with the CCI 450 and BR4 has the thickest cup in small rifle primers so I can see why it is the recommended primer. The Winchester primer has a thickness of .021, which to me is a significant difference from the 7 1/2. The Federal 200 has a thickness of .019, even less than the Winchester; the 205M has it at .0225.

I do not own a 454 Cassull and I do not handload for it. On the other hand I have had Remington 6 1/2 primers pierce on me and their thickness is .020 inch.

So in order of thickest to thinnest:

Rem 7 1/2: .025
CCI 450 & BR4: .025

Federal 205M: .0225

Winchester: .021

Rem 6 1/2: .020
CCI 400: .020

Federal 200: .019


Jul 14, 2009
Northern Lower MI
CCI pistol primers are notorious for being very hard. If you have a gun that has a light primer strike, it could cause some problems. 2 Taurus' I had (a 445 and 450) would do this on occassion w/CCI primers only.

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