Primer Accuracy?

Is there a difference in accuracy between the primer brands?  (It's easier for me to understand the accuracy impact of casing, powder and bullet.)  I understand functioning may be effected by a harder or softer primer brand, but I'm interested in the effect a primer may have on accuracy. 

Has anyone out there found one primer over the other being more accurate?

I'm not certain of impact on accuracy, but some primers have hotter ignition. WLP are hotter than Federal. Last winter a HM shooting next to me decided to use up some Federals he had and used the same load he was using with the WLP he normally loads with. He had all kinds of cycling problems (short stroke).

- Dave

Interesting u ask.

Today I was trying out some 185 loads. 4 " groups with silver primers.

In frustration I shot 3 rounds with a brass colored primer that went into a half dollar at 50 y.

I have no idea what primer that was! So much for accurate data collection!

There can be.  Rifle shooters have found the most consistent primers to be standard and bench rest primers.  Magnum primers can really mess up group sizes.

Silver was probably cci or federal brass colored is likely winchester which is hotter as it is for use with all loads including magnums.

I was thinking CCI.

Now I get to start all over because I tool record keeping shortcuts!

dsandula wrote:NRA Classification: Sharpshooter

Nope. You are wasting your time thinking about primers.

Bullseye pistol is a game of trigger control. Work on educating your trigger finger.

I think I'll just leave the primers out then....

james r chapman wrote:I think I'll just leave the primers out then....

Start by doing that half the time; that will certainly learn you something about your trigger control. 

I loaded some 200/3.9 BE with WLP and the same with Wolf primers.  The WLP are my usual load and worked fine.  But the Wolf primer loads were lucky to even get to the target.  Much weaker those Wolfs are

Interesting there was not a lot of feedback to my question.  It seems primer's make little difference in our sport, unless you go with "off" brand primers like Wolf.  That's been my experience, just thought I'd run it by the group.

john bickar wrote:

james r chapman wrote:I think I'll just leave the primers out then....

Start by doing that half the time; that will certainly learn you something about your trigger control. 

Touché

I did do some testing of primers a number of years ago and found that they had quite an effect on the standard deviation when I chronogaphed them.  But, I also found that, unless the SD was really large, it didn't correlate with group size.

Hi Ed - Do you remember if the primer changes effected point of impact? If so, do you remember how much at 25 and 50 yards?

In .38 Special in revolvers, I have twice seen group sizes suffer from primer brand ONLY because the primer strike was out of spec too low.

They were CCIs. Accuracy drops off BEFORE "reliability" of ignition becomes an issue.

Another guy's revolver which was mis-firing close to 25% with CCIs but FIRING 98% (misfire 2%) with Federals* was less accurate than he remembered it being before, with the Federal loads.

Me, I saw the accuracy drop-off myself after swapping to a strain screw from a guy's parts bin that had been shortened. Just a little too much.

But unfortunately for the OP, I have never noticed an accuracy difference in pistol ammo between the two primers I use, Winchester and CCI.



*Boy, that guy was PROUD of his "target-tuned" Colt's light trigger job!

Grumpy:

You are dead on with the accuracy dropping before reliability.  I have seen it and intentionally caused it while also shooting over chronograph on a ransom rest. The velocities started going all over the place in conjunction with the groups going to pot as the strain screw was backed off.

In regards to rifle shooters, one should not generalize.  I found CCI small rifle magnum benchrest to shoot just awesome with great groups and better extreme spreads and s.d. with them.

Also, I have been using Russian primers for nearly 14 years now in a 6mmXC cartridge (similar to .243 in performance and internal ballistics). The first primers were the ones that Bob Jensen imported in the original white with orange and green marked boxes, then as imported by PMC, and most recently Wolf. I believe that the TULA plant primers are different, but cannot say. The Russian made Large Rifle primers work great. The magnum (Russian made) primers seem to perform better....so far. The best thing is that so many have turned up their noses at them in the past and the price and availability (prior to Ukraine and Crimea mess) has been better than the other brands.  
Every new sleeve of primers I get, I test. I think it is the only way to know for sure.

-Ron