Does anyone know of any serious tests of the effects of cleaning or not cleaning the primer pockets on accuracy and reliability of cartridges?

I keep reading of those who don't clean primer pockets and it is very appealing to me. Do match shooters all clean their primer pockets?

I don't know about match shooters. I always clean mine, for both pistol and rifle. I believe that at some point the build up will affect primer seating.
Peter.

I used to clean my pp's religiously.

Then, one day, I just decided not to. I have some .22-250 brass that have been through 3 annealings since new, so... 20 loadings? I have yet to clean the pockets, and they are no less accurate than day one


BTW, I tumble before I deprime, so the pockerts aren't even getting cleaned during tumbling

I clean my rifle brass but not my pistol stuff.

Same as ChartieHo. Never a loss of accuracy or miss fire and sure saves time.

i will half to agree with peter. i clean all mine after ever resizing. i use a very small screwdriver

I quit cleaning them quite a while ago, never seemed to make much difference one way or another.

I deprime and use a ultrasonic cleaner, so I clean by default. I doubt it makes much if any difference as long as the primer seats properly. I think spending more time keeping the bore of the gun clean will yield a lot more in the accuracy department IMHO.

I've never found any difference in that. It appears that the primer residue is so thin and brittle that it doesn't interfere with anything and doesn't seem to build up with repeated firings.

I normally clean the pockets anyway. It's easy, fast, cheap and can't hurt anything can it?

I always clean them with a little tool I made from an old pencil sharpener. It's so quick and easy, there is no reason not to do it. I get a feeling of having done all I can do to prep the brass when I clean the pocket...

Hey Red, A lot of folks do not clean Primer Pockets and get along fine - I'm not in that group. I do clean mine.

It is always the little tedious tasks that are the most aggravating. But, I want the most "Confidence" possible in my Cartridges, so I do those small tasks.

Best of luck to you.

I deprime, resize, and then tumble so the depriming and tumbling seems to knock all (most) of the crud out of the pocket except for a light patina. I don't go poking around inside of the cases for those ubiquitous little trapdoors that worry everybody either.
I don't know how serious you would call it but once I took 25 cases and uniformed the pockets and took 25 random cases without uniforming the pockets. The cases were already 1X fireformed to the rifle I was using. I fired 5 groups of 5 from each sample and then reloaded the cases. The uniformed cases had the pp's cleaned. Everything else was the same. In all, eash case was fired a total of 5 times. No effort was made to segregate the cases within the samples, they were just re-prepped, reloaded and put into seperate loading blocks and taken to the firing line. I was using a rifle with an established track record and there was no discernable difference between the aggregate groups. (It might have gone easier if I had 200 yards but I only had 100 yards and trying to measure one raggedy hole against another raggedy hole can get tedious.) And so, I stopped (or never started) cleaning primer pockets.
Quite a few of the bench shooters have gotten away from primer pocket cleaning. In fact, away from quite a bit of the anal stuff they were doing "because everybody else was".

I "clean" my rifle brass by using one of those carbide tools designed to cut the primer pockets to a uniformed depth.
Each time the tool is employed it cleans out the dirt and a small amount of brass.
I doubt if it contributes to better accuracy but it makes me feel better.

Hi!
I decap before I tumble my brass with a cheap-o Lee Reloader press and universal decapping die (I don't like the primer residue building up on my good press). So, by default I clean all my primer pockets with the tumbler... so I can't say whether or not it affects accuracy. I sometimes have a case or two that have more residue than the tumbler can adequately clean, so I run a primer pocket cleaner in those. One thing that I've found that absolutely DOES affect accuracy is to uniform the flashhole... I like the Haydon and Lyman uniformers, they both do a great job and it definitely does affect the resulting loads. I didn't used to do this, but after I started uniforming flash holes on my .243 brass, my groups tightened probably 1/4" on average.

My bug against decapping first and then tumbling is that the walnut crunchies invariably find their way quite tightly into the flash hole. Then I have to run them through the resizer anyway to bring them back to spec, so why do it twice?

One of my tricks to is tumble, spray lube with cheap Dollar Store cooking spray, resize, wash the lube off in hot water and dishsoap with lots of old rags and a hefty helpin' o' elbow grease, rinse clean, then fry the cases at a low temp in a stainless steel skillet with a thin bottom. I can dry them completely dry this way in about ten to fifteen minutes. It's quick, it's easy and it works. The cases come out lookin' real nice...

quote:

My bug against decapping first and then tumbling is that the walnut crunchies invariably find their way quite tightly into the flash hole. Then I have to run them through the resizer anyway to bring them back to spec, so why do it twice?

When you pull the brass from the tumbler just use a bent paper clip to knock out the small piece that might get lodged.maybe 1-3 out of 10 do I have to do this to.

Cal30

I shoot 3,000 plus round per year of all size rifles and have for years. I have yet to resize a primer pocket or clean one except when I tumble my resized brass after depriming. I used the corn cob, then got smart and tired of picking it out of the primer pockets and went to Walnut Medium the flows through the primer pocket hole thus cleaning it as well. I also use the tumbling for cleaning the brass instead of rubbing it down with a rag after resizing. When you shoot as much as I do, you find ways to speed things up a bit. Good shooting.