Pistol primer pockets

[RMH]

When priming pistol brass with the RCBS hand priming tool I have noticed that some require very little pressure to seat while others a lot more. This is also the case with once fired brass with the same head stamp. My question is how do you tell when the primer pocket is too loose to be safe?

 

[otisrush]

I don't know if this is wise or not......but this is what I do.... (I, too, use the RCBS hand priming tool.)

I have a "looseness limit" defined (loosely ) in my head. If something feels too loose for long-term use I mark the head with a Sharpie, but I load the case anyway. When I see that case come through my decapping process I toss it in the trash. But as I said, I don't have a quantitative way to define what is too loose.

So far this has worked. I haven't had a case that had such a loose primer pocket I felt the need to take that live primer out and throw the case out right then.

 

[ArchAngelCD]

It's really a feel thing. When you are doing case after case and one feels like it goes in much easier that is the last time you should prime that case. Mark the case and toss it in the scrap bucket after you shoot it.

Of course if a primer falls out the pocket is too loose lol...

 

[243winxb]

If the primer seats without tools, its to loose.
Put a primer on a hard flat surface. Hold brass with thumb and finger. Slowly try to seat the primer.

Wear eye protection and keep face away from the case mouth. KABOOMS happen.

 

[rfwobbly]

Very small changes in the primer pocket cause big changes in the seating "feel". Primer pocket looseness can be due to manufacturing, or the result of the case being reloaded over and over. However, modern gun design makes it nearly impossible for the primer to be a danger once the cartridge goes into battery. The real concern is that the primer may fall out before the cartridge enters the chamber and jam the mechanism during rapid fire. (As in pistol competition.)

When a primer pocket seems to be too loose, I carefully and slowly offer the cartridge case up into a universal depriming die. Holding the case by the rim, if the primer can be unseated with a gentle two-finger push, then the primer might also fall out on its own. Loose cases go immediately to the recycle bin.

 

[Blue68f100]

If I can push them out by hand they go into the recycle bin. I use a universal depriming die to test with. Some times switching to a different brand of primers extends the life of the brass a few more cycles.

 

[goldpelican]

If I can push them out by hand they go into the recycle bin. I use a universal depriming die to test with. Some times switching to a different brand of primers extends the life of the brass a few more cycles.

That's an interesting point - are there known brands of "loose" and "tight' primers? SAAMI specs allow 0.002" tolerance in primer diameter for SR and SP - this chart on photobucket shows some measured diameters of various brands:

http://photobucket.com/gallery/user...vUHJpbWVyZGltZW5zaW9uc196cHM3OTQ5OWQxZi5qcGc=

Shows that Federal 200 SR primers are potentially wider than CCI 400 or Winchester SR - so Federals may allow you to extend the life of a loose pocket. But that's changing your load. Depends how valuable your brass is.

I recently ran into the problem where decrimping with a countersink didn't remove sufficient crimp with "circular" crimps on Federal 223 brass - some pockets were that tight that I actually slightly crushed a few primers with a hand primer, but other cases primed normally. A shave more reaming may fix them on the next load - I'm going to borrow the trick of a Sharpie on the case head to mark them as needing more decrimping.

 

[Blue68f100]

I mainly use CCI #41 and Rem 7 1/2 primers. All my brass is LC except my Lapua match brass. The load does change slightly between the 2 primers. Rem 7 1/2 gives me the best group with Lapua brass but after 10 cycles the primers are too loose. The #41 fit good, which gives me a few more cycles before the brass goes into the scrap.

There was a thread on this forum that covered which brands seam to be loose and which brands were tighter.

For hand gun primers I use Win, which is one of the larger ones. Which is all I have right now. In handgun if you don't switch between std and mag there is very little difference.

 

[hdwhit]

RMH wrote:
My question is how do you tell when the primer pocket is too loose to be safe?

I use a hand priming tool. If I have a primer go in too easy, I simply take the primed case, beat the case head on the bench and then run my finger over it to see if the primer has backed out or if it is still below the plane of the case head. I trust my finger to be a better sensor for such movement than my eyes. If the primer has backed out, I pop the primer out with a universal decapping die and re-use it while discarding the brass. If the beating has not caused any perceptible movement, I load it and rely on the fact that a significant portion of my brass is "lost to the weeds" each time to make sure that any brass that is sound when I start using it will be lost before it can wear out.

 

[mdi]

"Loose" primers can cause "blow by" and damage/etch bolt faces, just like pierced primers. It is a "feel" thing and it's better to err on the safe side. If a primer seating feels too loose, just set the case aside or deprime it and toss it. If you are scrimping on brass and want to make sure, look at this gauge, a Go/No Go type plug gauge; http://bulletin.accurateshooter.com/2014/12/primer-pocket-gauge-cool-tool-checks-for-loose-pockets/

When I start reloading a new to me cartridge I make it a point to acquire a lot of brass so if there is any question about the condition of the brass, I can set it aside for future consideration, or toss it. I'll still have a lot of cases to reload

 

[Sunray]

In all likelihood a pistol/handgun case will have cracked its case mouth into the scrap bin before the primer pocket will distort too much.
It really shouldn't take a great deal of pressure to seat a primer anyway.

 

[Walkalong]

Something you develop a feel for over time.

 

[Reloadron]

It's really a feel thing. When you are doing case after case and one feels like it goes in much easier that is the last time you should prime that case. Mark the case and toss it in the scrap bucket after you shoot it.

Of course if a primer falls out the pocket is too loose lol...

and

Something you develop a feel for over time.

I believe that pretty much covers it. Seating primers is just one of those task we develop a "feel" for and the more we seat the more we know what is a good seat verse a poor (loose) seating job. It's just one of those things which happens as a result of repetition.

Ron

 

[Hokie_PhD]

and

I believe that pretty much covers it. Seating primers is just one of those task we develop a "feel" for and the more we seat the more we know what is a good seat verse a poor (loose) seating job. It's just one of those things which happens as a result of repetition.

Ron

I agree
When I started I had no clue what felt right and what didn't

Thankfully CCI primers take a lot of abuse and I never had one go off while I managed them learning

 

[RMH]

Thanks for all the good advice. My wife and I shoot around 800 to 1000 rounds a month. Mine is a 9mm so it is no big deal to throw out suspect brass. Hers is a 380 and it launches brass into the next universe. So we come home with less 380 brass than we brought. I am trying to get as many safe loads as possible before I have to buy more. I think I will mark the looser ones so when I get them home I can punch out the spent primer. Then using my small hole gauges, mic the pockets to see if they are still within SAMMI specifications. That way I might learn the feel and gain experience. What do you think?

 

[ArchAngelCD]

Thanks for all the good advice. My wife and I shoot around 800 to 1000 rounds a month. Mine is a 9mm so it is no big deal to throw out suspect brass. Hers is a 380 and it launches brass into the next universe. So we come home with less 380 brass than we brought. I am trying to get as many safe loads as possible before I have to buy more. I think I will mark the looser ones so when I get them home I can punch out the spent primer. Then using my small hole gauges, mic the pockets to see if they are still within SAMMI specifications. That way I might learn the feel and gain experience. What do you think?

Just a note, with semi-auto brass I can not remember a primer pocket becoming loose. You are more likely to lose them before the primer pockets are loose or the mouth of the brass splits.

With revolver brass again I can't remember ever having a primer pocket go loose before the mouth of the case splits. As for splitting, that is also rare and I have loaded some .38 Special brass in excess of 40x.

Rifle brass is much more likely to develop loose primer pockets than most any handgun brass. Maybe the .460 Magnum will because those cases withstand the same pressures or higher than most rifle cases.

I would not worry too much about loose primer pockets. As for the .380 launching brass into orbit, you could lessen that by changing the recoil spring to a stiffer one.

 

[Dudedog]

Different brass has a different feel, hard to say by feel alone. Some primers run slightly larger and some brass slightly smaller so get the two together and the seating feels really firm and other good brass will feel loose compared to that.

After you have loaded more you will get a better feel for feel, not much help I realize.

I will probably get hammered on this one but for semi auto pistol brass I don't think it's worth the time to measure them, if the primer passes the above tests but you still think the cases pocket is getting loose mark the case with a sharpie on the base and just toss it if you come across it in the brass you pickup. I have never had any issues with pockets in 9mm, .380 or .45 case necks usually split first in high mileage cases. (of course I am not loading really hot either)
.357 and rifle brass are a different story.

 

[Ole Joe Clark]

If the primer falls back out, it's too loose.

 

[mdi]

I started reloading with a Lee Loader. Kinda hard to develop "feel" with an 8 oz mallet...

 

[FROGO207]

I use a universal decapper in my hand and the brass in the other. If I can push the primer out of the brass it is too loose. I also use the trick of using a larger diameter primer to extend the number of times I can load my brass. This is usually for rifle brass as handgun brass does not develop loose primer pockets as a rule though.