What difference does a primer make?

[Wingy]

Following on from another thread "primers" where talk was in relation to a shortage of a particular primer, got me wondering. What difference does it make & how noticeable?
I've not been reloading that long & when I started I went to the gunshop & asked for advice for a 100 grain .243 for my rifle. I came away with 2 types of bullet, 1 powder & 1 type of primers.
I set up ladder scale loads & found what I liked so stuck with it. Question is if I keep all other factors constant,
Brass, powder & bullet what difference would changing the primer have? Is the primer just a source of ignition or is it more complex than that?
I was using federal LR match primers now have standard federal primers
Wingy

 

[Ranger22]

We had factory rounds with different primers used. All the rounds we have used had the same bullets, powder and cases. The original rounds grouped half inch, the batch with different primers grouped, if you can call it that, three inches out of my rifle and five inches out of another. What the other primers were I don't know but they certainly made a big difference, we are now back onto rounds the same as the original ones and back doing half inch groups

Al

 

[splash]

Do a search on Google, I cant recal the link but there is a load of pictures of different primers in action ! you will be surprised they range from an ignition to a 2" flame.

Think its quite old though

 

[enfieldspares]

I have tried, over a chronograph, Remington and CCI (both STANDARD) Large Rifle primers in my .270 WCF with every other element of the load the same. I found that the velocity spread was the smallest with the CCI primers and that also the acheived velocity was the greatest. I don't have my Game Book with me as I write this but can say that the better primer of the two was the CCI.

I have also over a chronograph tested Remington and CCI (both STANDARD) Large Pistol primers in a twenty inch barrel Winchester 94 in .44 Magnum and in that the highest velocity was given by cartridges loaded with the Remington primer. Again cases, powder, bullet and how it was seated and crimped were the same in each batch.

So the real test is load a batch identical in every way except for the primers and chronograph them.

 

[6pointer]

I had the same as Ranger22 i had CCI,s the gun shop ran out and gave me a box of Remminton BR Primers feck i near failed the shooting test.So primers are a big factor.I looked around for CCI and got back on track.

 

[8x57]

We had factory rounds with different primers used. All the rounds we have used had the same bullets, powder and cases. The original rounds grouped half inch, the batch with different primers grouped, if you can call it that, three inches out of my rifle and five inches out of another. What the other primers were I don't know but they certainly made a big difference, we are now back onto rounds the same as the original ones and back doing half inch groups

Al

I don't doubt what you say Ranger but surely the loads must have been different in some other way and not just the primers to give such a difference? Lots of ammunition from the same manufacturer can after all vary significantly in their results.
I say that because I have tested loads using the same components in every way apart from the primers and have had varying results not only of accuracy but of velocity as well, but the difference has never been as dramatic as that. I have one reloading manual that actually claims that different primers make no significant difference but that manual is the exception to the rule and all others claim that it does.

 

[Ranger22]

No just the primers, everything else was the same.

Al

 

[8x57]

Perhaps it was just a bad lot off ammo?

Not quite the same but just to show how lots/batches vary our club purchased an initial 10,000 Geco .22lr rounds after a trial evening hosted by the RUAG representative. The first 10,000 were brilliant and we decided to continue buying that ammo in the future as the price was right also. The next batch that we bought certainly didn't give the same accuracy in fact in the same rifles it gave much larger groups, probably twice the size. We were able to confirm this by going back to some of the original batch that one of the club members still had. Now you would think that the quality control would ensure consistency from batch to batch but obviously not. It could be the same with centrefire ammunition. In fact I have heard that the NRA had to return the last batch of 7.62mm to RWS because of problems with that batch of ammo.

 

[Wingy]

Perhaps it was just a bad lot off ammo?

Not quite the same but just to show how lots/batches vary our club purchased an initial 10,000 Geco .22lr rounds after a trial evening hosted by the RUAG representative. The first 10,000 were brilliant and we decided to continue buying that ammo in the future as the price was right also. The next batch that we bought certainly didn't give the same accuracy in fact in the same rifles it gave much larger groups, probably twice the size. We were able to confirm this by going back to some of the original batch that one of the club members still had. Now you would think that the quality control would ensure consistency from batch to batch but obviously not. It could be the same with centrefire ammunition. In fact I have heard that the NRA had to return the last batch of 7.62mm to RWS because of problems with that batch of ammo.

Yes I was using Geco .22 in my CZ 452, then about 2 years ago Geco changed their ammunition, staff at the gunshop told me this as I went to buy more. It's never been the same since
Wingy

 

[JMS906]

Perhaps it was just a bad lot off ammo?

Not quite the same but just to show how lots/batches vary our club purchased an initial 10,000 Geco .22lr rounds after a trial evening hosted by the RUAG representative.

Geco is budget ammo. It's cheap for a reason. If you want something better then you have to pay more. Geco is fine for shooting from cheap semi-autos and for plinking. It's not target ammo.

-JMS

 

[8x57]

Yes we were aware of that JMS, we bought it for the semi-autos, none the less it shot very well through some bolt action rifles. We are currently using SK ammunition through these rifles. Obviously the serious gravel bellies as opposed to the gallery rifle guys use other ammunition such as RWS match or Eley Tennex or Match.

 

[enfieldspares]

Herewith my figures. I won't give the powder loads, but will give the powder brands:

.270 WCF in 23.5" barrel BRNO ZKK 600
150 grain Hornady - XX.X grain Hodgdon H4831 - CCI LARGE RIFLE STANDARD - Average 2809 fps - Mean Deviation 30 fps
150 grain Hornady - XX.X grain Hodgdon H4831 - REMINGTON 9 1/2 LARGE RIFLE STANDARD - Average 2803 fps - Mean Deviation 116 fps

.44 Magnum in 20" barrel Winchester 94
245 grain cast lead SWC/Keith - X.X grain Hercules Green Dot - CCI LARGE PISTOL STANDARD - Average 904 fps
245 grain cast lead SWC/Keith - X.X grain Hercules Green Dot - REMINGTON LARGE PISTOL STANDARD - Average 922 fps

Powder weights, cases, bullets remained the same only the primers changed. The Winchester was chronographed to see if it was legal within the range velocity and energy template...so indoors. The BRNO ZKK 600 was chronographed outdoors...on a mild day.

 

[bazil]

Oi wingy without one it won't fire Doh! Bazil lol

 

[DCG]

I can remember learning this lesson when shooting pistols years ago, doing tests on a 38special load in a 686 revolver using a Ransoms rest, changing just the primers made a (to me) startling difference in both group size and mean point of impact.
I've recently been developing a new load for my 7-08 using reloader 17 and 140gn nosler balistic tips, just changing the primer from Remington 9 1/2 LR primers to cci br2 brought the group size down from 1 1/2" to 3/4 inch.
One good tip is, if you're regularly getting two bullets printing together and one away on its own, in your groups, try changing the primer.
Regards
dcg

 

[Wingy]

Thanks for the replies, I never thought it would make that much difference, but just goes to show with collective experience from SD members, paints a bigger picture. Think its time to start a little more experimenting with other components (when they start to appear in the shops again)
Wingy

 

[Muir]

I am surprised this has gone beyond the simple answer of "Yes" considering that the quality and properties of ignition has always been considered a foundation of load development. I have had CF rifle loads go from half minute to 1.2 MOA with change of primer alone. That's why I always figure that a new primer means (possibly) a new load.~Muir

 

[MACKY]

One of the lad I shoot with uses a Blaser in .270, with .130 gr rounds not going to name any makes.
He was 1" high with one batch of amo, when he changed to a diffarent batch he was shooting 1" low & 2.5" right only diffrence was the primers.

JM

 

[majex45]

Primers can make a big difference. I have limited experience of reloading for rifle where things are much more critical but I have used many types of primers in pistol ammunition.
Federal were always considered hottest and had the softest cups. They would always ignite the powder even when used in "tricked up" revolvers where the hammer barely kissed the primer.
CCI were much harder but were very consistent. Remingtron were unreliable, whenever I've had a total failure to fire (hitting it several times) it was with Remington - the same applies to their .22 ammo.
I have some primers beginning with C (made in Bosnia Hertzegovina) which I think are made from old railway lines they are that tough. They are also a fraction oversize so take a lot more effort to seat than normal (in a Lee priming device).
Just my two penn'orth,