Primer manufactures are different

[zchaparral]

I was recently priming some .223 brass with Remington small rifle primers. I found a large amount of them were fitting very easily (loosely). I picked up some CCI primers the next day and found they have a much tighter fit. All of them so far. I am posting this because I have read similar posts questioning loose fitting primers. I have never measured primers but spec charts I have seen people post very a significant amount.

 

[Reloadron]

Primers should be made to specific dimensions set forth by SAAMI.

We can see where a primer could be in specification on the low end and a pocket on the high end resulting in a loose fit. We can measure a primer OD and the pocket ID and get an idea as to how the fit will work out. Even primers by the same manufacturer may vary lot to lot of manufacture. As long as the primers fall within the window they meet the specification. The same is true of the primer pockets.

Ron

 

[Bart B.]

Loose primers can be locked in place with a thin bead of super glue dabbed around their top to the case head.

 

[bbqreloader]

ok, so I guess my question is, if the small and the larges are the same size, is it the compound inside that makes the difference? I would guess it would have to be as there are 4 regular choices besides the 50bmg and shotgun/muzzle

 

[JimKirk]

You have primer cup material thickness, cup hardness, compound differences in those that are the same size in diameter ... but also height differences in large pistol and large rifle ....

 

[Reloadron]

You have primer cup material thickness, cup hardness, compound differences in those that are the same size in diameter ... but also height differences in large pistol and large rifle ....

Yes, and during a discussion I asked CCI about a few things to get them resolved. Here are a few of the Q&A:
Question: Are CCI 400 small rifle and CCI 550 small pistol magnum actually one in the
same primer with identical thickness and charge?
Thank You

Answer:
Ronald, these are not the same exact primer and you should never mix
reloading components.

The discussion focused on a claim that since small rifle and small pistol share the same dimensions that they were the same primer. They obviously aren't.

Question:
Regarding CCI #34 primers. The question has come up or it has been stated that CCI #34 primers are the same thing as CCI 250 Large Rifle Magnum primers. While I know the CCI #34 is a magnum primer I believe it is not the same as other large rifle magnum primers in that it has further reduced sensitivity. Would that be correct and is the priming mix different than standard large rifle magnum primers.

Thank You

Answer:
Small rifle primers
#41......................................Mil. Spec. primer, thick cup, magnum primer charge, angle of anvil change.
BR4.....................................thick cup, standard anvil and standard priming mix held to a tighter tolerance.

The last answer runs with what Jim Kirk had to say. We select a primer based on load data. My old Speer #12 even went so far as to mention using a magnum primer with certain powders. Primers are selected based on the powder they need to ignite.

ok, so I guess my question is, if the small and the larges are the same size, is it the compound inside that makes the difference? I would guess it would have to be as there are 4 regular choices besides the 50bmg and shotgun/muzzle

Small rifle and small pistol, standard or magnum share the same dimensions but that is as far as it goes. Their thickness, mixture, and things like anvil angle are not the same. While in a few loadings people will share them (interchange them) I will not suggest that for someone just learning about primers.

Ron

 

[bbqreloader]

You have primer cup material thickness, cup hardness, compound differences in those that are the same size in diameter ... but also height differences in large pistol and large rifle ....

Jim, missed the height diff in the lrg pistol and rifle. Thanks for reply I was just curious what the difference between small rifle and pistol, ie compound, anvil etc that would seperate the two. Thanks

 

[RussellC]

I was recently priming some .223 brass with Remington small rifle primers. I found a large amount of them were fitting very easily (loosely). I picked up some CCI primers the next day and found they have a much tighter fit. All of them so far. I am posting this because I have read similar posts questioning loose fitting primers. I have never measured primers but spec charts I have seen people post very a significant amount.

I have definitely noticed this with small pistol primers. Where Winchester I usually use are loose, CCI (also tula) fit tighter. There is a difference.

Russellc

 

[macgrumpy]

Try checking the inside diameter of the primer pocket before you jump to the conclusion that the primer is at fault, primer pockets expand over time and can become oversized by a few thousandths of an inch from normal use.

 

[someguy2800]

I pretty much stopped using cci primers because so often they are a pain to get them seated into tight pockets. For any of my high volume reloading calibers (223, 9mm, 38 special, 357) if I find a case that is either too hard or too easy to seat a primer I just chuck them in the trash so I don't have to deal with it next time.

 

[mdi]

Check the chart for primer dimensions. A .002" tolerance in diameter will be felt when inserting the primer. There is a phenomenon called "tolerance stacking" which will affect primer (or anything) fit. If the primers from a certain manufacturer are on the small side and the primer pockets are on the large side, the fit will feel looser, but everything is OK, in tolerance...

 

[Rule3]

I was recently priming some .223 brass with Remington small rifle primers. I found a large amount of them were fitting very easily (loosely). I picked up some CCI primers the next day and found they have a much tighter fit. All of them so far. I am posting this because I have read similar posts questioning loose fitting primers. I have never measured primers but spec charts I have seen people post very a significant amount.

What perhaps is not taken into account is the above "some" Is that 10 or 100?

What brass is it? How many times was it reloaded? Was it 223 or 556. All the same headstamp? If military had the primer pocket been reamed or swagged??
Just more variables to throw out there,

 

[Nature Boy]

Being a little too aggressive in swaging/removing crimp could lead to pockets that are too large