How do you tell if primer pockets are too big ?

[watkibe]

I usually throw out cases if the primer seats too easily. Of course that means throwing out the new primer I just put in the case. As hard as primers are to get these days, I hate to do that.

How do you tell if the pocket has stretched too much without seating a primer ?

[jcwit]

Why oh why do you not gently push the unfired primer out before tossing the case,

Primers ignite from IMPACT not from PRESSURE. Have done it hundreds and hundreds of times.

[trk]

Definately when you open the breech (falling block) and the spent primer falls out!

[RayinNH]

Absolutely save those primers...Ray

[454PB]

Not to "preach", but expanding primer pockets is a sign your loads are too heavy.

[lylejb]

Just a thought. I haven't actually tried this, but if you have access to a machine shop, turn the end of a piece of rod to .001- .002 under primer size. Since primers are a press fit, if this fits easy, the primer pocket oversize. You might have to play with the size a bit to get it right.

This would be a "no-go" gauge of sorts.

[Bad Water Bill]

You might try a # drill. I used to have a set but no longer so can not chech for you. I am sure one of our many lathe people can give a Y or N and size if possible.

[rob45]

To the best of my knowledge, SAAMI puts a spec on the depth, but not the diameter. So it seems dimensions for diameter are pretty much assumed by the people making the brass and the primers.

Nominal diameter dimensions for the primers (not the pockets) are .175" for the SP/SR, and .210" for the LP/LR.
IME, the CCIs not only are slightly harder, but also slightly larger. So your dimensions are going to be based upon whose primers and brass you're using, and even different lots.
Likewise, the brass manufacturers are free to produce the pockets to the dimension they feel provides the proper interference fit. As all manufacturers (and different lots from the same) have different "hardness" on their products, one batch of brass may develop loose pockets sooner or later than another.

Loose pockets can be caused by a variety of factors; the first thing I would investigate is how hot the load is. If the load is known safe, then other areas can be checked.


Sadly, all brass eventually wears out. If one is shooting an expensive cartridge, or has put considerable time and effort into the brass (forming, neck turning, etc.), then the option exists to reswage the pocket. I'm not talking about the type of swaging that removes a crimp; I'm talking about making the pocket small enough to hold the primer again. It's a process that may or may not be worth the effort, just depends on what the value of your brass is.

http://castboolits.gunloads.com/showthread.php?t=69231

Good Luck.

[EMC45]

I reprimed some brass for a buddy and could almost reprime with thumb pressure!!! Hot load!

[trk]

Not to "preach", but expanding primer pockets is a sign your loads are too heavy.

OR that you've mistakenly annealed the brass WAY too far down to the bottom! ;)

[watkibe]

Thanks for the input, guys. Using a pin guage did occur to me, but the issues mentioned above about pocket and primer specs differing by manufacturer make it hard to decide what size pin gauge to buy. These cases were just old (I lost track of how many times they were reloaded...), not loaded too hot. I do like the idea of punching the primer back out, although putting it into practice might have difficulties. I have enough trouble handling those pesky little primers without dropping them as it is, I don't know how well I would do catching the primer if I removed it. Besides, primers are "armed" when they are seated by pressing the case into contact with the pellet and the anvil. Hmmm......

[R.C. Hatter]

:groner:Throwing out good primers is a waste of money. Gently press them out of suspect brass and retain them in a separate container from your "good" primers.
They can be used in test loads where only a few at a time are needed, or for plinking loads. It can be easily and safely done if you are careful. I've done it a few hundred times myself.

[mooman76]

What kind of primers are you talking about? CCIs and Wolf primers are a little tighter going in than Win & Fed.

[leadman]

When I deprime live primers I empty the primer catcher and put a rag in my hand to make sure it doesn't bonce out the front. Make sure you have all the safety gear on just in case.
I'm using an RCBS Rock Chucker so sometimes the used primers do bounce out of the catcher.

[lwknight]

If you have to push the primer out , its probably a good fit. I'm confuse.

[Lee]

If it says "A-MERC" on the head stamp..........:-P

[RollerCam]

If it says "A-MERC" on the head stamp..........:-P

From the A-Merc website: "Over the coming months AA will be increasing its production capacity, which will lead to greater presence in the market."

It'll also lead to a greater incidence of me at my local firing range, squinting at the headstamp and saying "Damn! Another A-Merc!"

At least with Blazer aluminum cases, you know not to squat down and pick them up.

[Multigunner]

A primed case you plan to toss is at least good for dry firing and checking striker fall.
I hate to loose a primer but I don't think a primer once seated and then pushed out would be as likely to give consistent ignition.

To some extent seating the primer is the final step in sensitising the compound, a bit of preload. The reason consistent depth is recommended.

Using a compromised primer is a waste of propellants and lead.
Only good use would be in fireforming a case, where good accuracy is not a big issue.

[DLCTEX]

I have removed 100's of primers over the years and reuse them with no ill effects. If the anvil stays in place it's good to go. You don't state what brand of primer you used, but the CCI and wolf mentioned may fit tight.

[jcwit]

A primed case you plan to toss is at least good for dry firing and checking striker fall.
I hate to loose a primer but I don't think a primer once seated and then pushed out would be as likely to give consistent ignition.

To some extent seating the primer is the final step in sensitising the compound, a bit of preload. The reason consistent depth is recommended.

Using a compromised primer is a waste of propellants and lead.
Only good use would be in fireforming a case, where good accuracy is not a big issue.

Not true!!

Have removed live primers hundreds of times.
Primers are ment to go BANG.
Have yet to not have a reseated primer go BANG.

Only time I'd deviate from the above is at a bench rest match, but thats a whole different ball game.

[DLCTEX]

Sounds as if some of you need a Lee Classic press and catching those primers would be no problem.:razz: