Are all small pistol and large pistol primers the same?

SLT223

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Aside from magnum primers, is there ayn difference between CCI SP and Winchester SP, or say Winchester LP and Remington 2 1/2?
 
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Yes, they are different.

Different primers deliver different pressures and velocities. They are also different in terms of their physical properties. For example, some are easier to ignite than others and require lighter strikes than others.

In most instances, these are differences without consequence.

However, if you are working up max loads, primers can contribute thousands of pounds of pressure.

Read and follow the published data.
 
To be safe, you should always back off of your established charge weight a bit when switching primers and then work back up watching for any signs of excessive pressure.

That being said, I routinely change pistol primer brands in my range practice rounds for 9mm and .45ACP. I'll note that I am NOT pushing a load anywhere near max. If I were, I would decrease the charge weight and work up the load again.

This practice has worked satisfactorily for me for the past 35 years. YMMV.
 
Someone on here a while back posted a chart of relative primer energies of different brands of primers. I don't recall specifics, but do remember that standard small pistol primers are all pretty close in energy.

Aside from that, certain primers have reputations for being "soft" or "hard," which is how much energy is required to set them off(i.e. how hard of a hit from the firing pin). Federal has a reputation for "soft" primers while at least among the popular brands CCI is regarded as being "hard." I think the others fall somewhere between the two.
 
Agree with all the above. With the influx of foreign primers there are also some primers that are slightly larger/smaller in diameter and I've read that some may be difficult to seat. I haven't tried any of the foreign primers yet, so I have no personal knowledge. If you are considering buying some, it might be prudent to see if another forum member has tried them and if they encountered any problems before buying many thousand of them.
 
Yes, they are different.

Different primers deliver different pressures and velocities. They are also different in terms of their physical properties. For example, some are easier to ignite than others and require lighter strikes than others.

In most instances, these are differences without consequence.

However, if you are working up max loads, primers can contribute thousands of pounds of pressure.

Read and follow the published data.

It's a good question.

I agree with all, except would need to see some hard data or tests on how much they vary.

"primers can contribute thousands of pounds of pressure."

They deliver BTU's of energy but have not seen anything relating to that large of amount of pressure.??

CCI vs Win SPP do they vary that much?

Winchester LP are rated for regular and Magnum loads.
 
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There are slight diff, but unless you worked loads up to max with one brand, not really a diff. When working with max loads, everything matters; primer brand, case brand, even powder lots can be an issue at max loads.
 
There are slight diff, but unless you worked loads up to max with one brand, not really a diff. When working with max loads, everything matters; primer brand, case brand, even powder lots can be an issue at max loads.

Really, this is true of any load built to a stringent specification.
A way to illustrate this is to take a near min load for a rifle, and try to achieve the same velocity with any random primer on hand.
It can be interesting.
 
Really, this is true of any load built to a stringent specification.
A way to illustrate this is to take a near min load for a rifle, and try to achieve the same velocity with any random primer on hand.
It can be interesting.

Stringent specs & max loads, two diff things. While you may get less accuracy swapping a primer in a precision rifle load, swapping components on max loads can actually cause an over pressure vent. This may or may not be dangerous, but certainly not desirable.
When I am doing precision rifle, the last thing I will do, after the load is settled on, is swap 2-3 diff primer brands. Sometimes it matters, sometimes not. My 338-06 shows the most gain from a specific brand (cci br2).
 
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Winchester LP are rated for regular and Magnum loads.

As I recall from primer energy charts I've seen posted, most LP primers are pretty close in energy to SP Magnum primers.

I'll offer the following statement with the caution that although what I state below has worked for me, please don't take this as an advertisement or endorsement for you to do the same

With the energies in mind, I have used Remington LP primers in 44 Magnum with W296. I had no issues with this, and also had good standard deviation over the chrono.

With that said, I have switched over to using Winchester LP primers with my W296 loads in large primer cartridges. This really serves to purposes. First, it lets me use a "magnum" primer without having to keep a separate magnum primer on hand(plus is the primer specified in a lot of Hogdon load data). Second, since Winchester primers are brass and all the other brands I use are nickel plated, and W296 loads tend to be "max" loads for any given caliber, it provides an easy way for me to identify and distinguish max loads.
 
I interchange them without much concern. Other than Win LPP which can also be a Mag primer I doubt there can be much difference in energy provided. They all go bang. Yes there is difference in hardness but I would like to see an actual test showing the energy or pressure. Not just pictures of the flash which may indicate intensity.

Posted a question on another forum to see if anyone has any real data.

I only have the old CCI chart of their primers but this may have changed. Posted this many times
 
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Although I tend to use one brand and type of primer for each type of loading I do, I never really believed that primer brand made that much difference in metallic cartridges (shotguns are another story).

But I recently discovered that they can make a difference in black powder guns. I was sent one of the soon-to-be-released Remington Model 700 Ultimate Muzzleloaders that use large rifle magnum primers seated in shortened and internally altered centerfire rifle cases for ignition of up to 200 grains of black powder or substitutes like Pyrodex or Triple Se7en. The rifles come with 24 cases primed, of course, with Remington large rifle magnum primers.

I started out shooting it with the same bullet and propellant charge that worked best in my 209-ignition T/C Omega and was getting three to four-inch groups at 25 yards but didn't get concerned about such accuracy because, after all, it probably wasn't the "right" load for this rifle. But I couldn't get any holes in the target at 100 yards and was getting chronograph readings that varied by hundreds of feet per second. I quickly used those 24 cases and had to decap and reprime them for another go-round. As the primer flame travels through the breech plug like a normal inline muzzleloader and no actual combustion takes place in them, resizing is not required

For reasons I cannot recall, I have used Federal #215 large rifle magnum primers in my magnum rifles. Being all I had on hand, I used them in the muzzleloader cases and the weird groups and chronograph readings went away! I'm now working on trying to improve on 1.5" 100-yard groups with the bullet and propellant charge that this rifle seems to like best. Groups shot at 50 yards are literally one-holers!

For what it's worth to the smokepole fans on here, this ignition system really cooks! It burns so much hotter than 209-primed systems that the bore stays clean longer and it is capable of lighting off up to four pellets of black powder substitutes or 200 grains by volume of loose powder. I tried shooting it five times without cleaning and bullet #5 seated without a lot of extra effort on the rod. Three-shot groups with the barrel cleaned after each shot or left dirty are the same size and in the same place on the target.

If I hadn't seen it with my own eyes, I probably wouldn't have believed what changing primer brands did. Remington primers work well for me in handguns and they are all I use in my shotshells. Their factory rifle ammo, which I buy just to break in a new barrel and get a scope "on paper," always seems decently accurate for factory fodder. I don't know if this being a black powder gun made a difference or if I just got some bad primers but when my order of 72 more cases arrived, their primers were replaced with 215s before they were used.

Ed
 
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Back to the original questions. There are compositional differences existing among priming compositions depending upon manufacturer and primer type. But there is very little difference in ballistic performance among the same types of primers from different manufacturers, as things such as impact energy required for primer ignition are pretty well standardized within the industry. The whole business about Winchester having a soft primer and CCI having a hard primer, etc., is total fiction, promoted by those who have no facts to support the assertion, so long as the same types of primers are being compared. Rifle primers typically have heavier cup material to better withstand heavier pressures, and in some cases, such as CCI NATO primers, the primers are designed to require a heavier firing pin blow to prevent slam fires in semi- and full-automatic weapons. Regarding small rifle and small pistol primers, they are dimensionally the same and it's possible to use small rifle primers in small pistol cartridges (but not vice-versa). I have tested this extensively in .38 Special, and have found absolutely no difference in MV or grouping capability. However, a lighter firing pin strike may result in misfires if small rifle primers are used in a specific gun. I have had no problems with the use of small rifle primers in any of my revolvers. Not so with the use of large rifle primers in large pistol primer pockets. There is a dimensional difference, and a large rifle primer, when seated, will not seat flush with the base and will cause headspace problems. The use of a large pistol primer is a rifle case will work, but it is dangerous due to the higher chamber pressures involved in a rifle.

The most extensive treatment of primer technology is to be found in Frost's book "Making Ammunition." However it is currently out of print and copies are hard to find and expensive.
 
Although I tend to use one brand and type of primer for each type of loading I do, I never really believed that primer brand made that much difference in metallic cartridges (shotguns are another story).

Ed
What makes you think there is a diff? If it matters in SG, it matters in handguns, powders are very sim or identical. FWIW, doesn't matter in SG unless loading max, not unlike handgun or rifle for that matter.
 
Fred, I base that assumption (and without the ability to laboratory-test anything, that's all any of us can do) upon the miniscule changes in published loading data attributable to primer brand changes. Standard small pistol primers pretty much are standard small pistol primers and so forth. Also, I have seen no changes in chronograph readings or group sizes when I switch from CCI pistol primers to Remingtons. As I indicated above, I've never been much of a component swapper; I tend to find something in which I feel confident and stick with it.

Shotgun #209 primers are quite different in that loading data DOES change with primer brands. Remington and CCI standard 209s are considered the mildest while Federal 209As and CCI 209Ms are the hottest. Winchester, Cheddite, Fiocchi, Rio and the rest of the 209s fall in between those two extremes.

Ed
 
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The only difference I've noticed is between Winchester and CCI, the Winchester has a "squarer" cup shoulder, whereas the CCI is more rounded. I notice this when I'm loading up a primer feed tube. I have to get the tube exactly centered on the Winchester where I only have to be close on the CCI. For the pool players it's kind of like the difference between a snooker table pocket and a regular pool pocket. (how's that for an obscure description?) :D
 
Back to the original questions. There are compositional differences existing among priming compositions depending upon manufacturer and primer type. But there is very little difference in ballistic performance among the same types of primers from different manufacturers, as things such as impact energy required for primer ignition are pretty well standardized within the industry. The whole business about Winchester having a soft primer and CCI having a hard primer, etc., is total fiction, promoted by those who have no facts to support the assertion, so long as the same types of primers are being compared. Rifle primers typically have heavier cup material to better withstand heavier pressures, and in some cases, such as CCI NATO primers, the primers are designed to require a heavier firing pin blow to prevent slam fires in semi- and full-automatic weapons. Regarding small rifle and small pistol primers, they are dimensionally the same and it's possible to use small rifle primers in small pistol cartridges (but not vice-versa). I have tested this extensively in .38 Special, and have found absolutely no difference in MV or grouping capability. However, a lighter firing pin strike may result in misfires if small rifle primers are used in a specific gun. I have had no problems with the use of small rifle primers in any of my revolvers. Not so with the use of large rifle primers in large pistol primer pockets. There is a dimensional difference, and a large rifle primer, when seated, will not seat flush with the base and will cause headspace problems. The use of a large pistol primer is a rifle case will work, but it is dangerous due to the higher chamber pressures involved in a rifle.

The most extensive treatment of primer technology is to be found in Frost's book "Making Ammunition." However it is currently out of print and copies are hard to find and expensive.

Based on the above you are saying that Federal Primers will not ignite with a much lighter firing pin strike then the other brands? That there is no difference in the cup hardness of SP and LP primer brands? Why then do lightly tuned hammers on comp guns only fire with Federal Primers and why did CCI announce that they developed a softer cup for their primer?

Throw Wolf primers into the mix and they are much harder than Win or CCI primers. I have loaded thousands of them.
 
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