Uniforming Primer Pockets

C

cw308

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Deburring flash hole should only be deburred once to the case. Could the same apply to the primer pocket, goes the depth change with multiple firings.
 
Thank you Joe for getting to me. I uniformed my primer pockets every time I sized my brass, I changed my brass cleaning from dry tumbeling media, to wet tumbeling with stainless steel pins. The pockets come out spotless.
 
Using the Redding primer pocket depth uniformer for cleaning pockets after the initial depth reaming, I have removed additional brass from the bottom of the pocket, but can't really say if this is due to "primer pocket set-back", or perhaps having just not cut deep enough during the first pass through with the uniformer tool. But l would imagine that set-back is possible. However I only use the uniformer for Garand '06 loads, using only Federal brass that many dislike for being soft, and maybe that could contribute to set-back. Any set-back might just be confined to the center of the pocket rather than around the perimeter and not affect subsequent primer seating depth.
 
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C brave, Thant's for the info. Had a M1 Garand in the 70's picked it up for $ 100. Sold it to a friend for the same price 4 years later. I could kick myself every time I think of it. Very accurate.
 
Yes, no doubt we've all had several guns of one kind or another that we are kicking ourselves over and over again. One of mine was the $17 or so DCM .30 carbine still in cosmoline. The last one I saw like that had a $3,000 price tag attached to it so have had to settle for something less. But your friend thanks you.
 
yes, I Debur flash hole once per case life. But I I uniform my primer pockets every time after sizing brass. I dry tumble so I still have hard carbon in the pocket. After firing I feel that the web can be pushed back just slightly out of uniform. I use the 21st century primer pocket uniform tool and have it set to the lot of brass im using. I will find fine shavings after repeated firings. But this might not be necessary specially since your pockets are coming out clean with the wet system, but this is just the way I do it.
Tony
 
K9 fax, I preped my brass like you , tumbled with dry media , deprimed , cleaned primer pockets with uniformer, sized & trimmed every firing. Using this wet tumbler with SS pins I'm like a kid at Christmas with that special toy. Makes the brass like new, very easy to see any problems starting with the brass. Now with the pockets l still uniform but only one twist to check depth. I would think if from the first firing the cases would clean much quicker, I've been cleaning cases I reloaded 7 times with dry tumbler after 2 hours like new I was very surprised at the difference.
 
I took a set of 308 LC cases twenty + reloads in my M1a. The cases were lubricated so the sidewalls would not grip the chamber and cause case head separation. Somewhere around the 10th reload I noticed the primer pockets getting shallower. I believe that the case head expands outwards with enough reloads and that makes the pocket shallower. I got in the habit or reaming pockets each reload, or every couple of reloads, just to ensure that primers stayed below the case head. First reaming took out a lot of material but subsequent and repeated reamings, not so much.
 
cw308,
what do you have as far as the SS pin system? im going to look into this, but don't know what direction to go.... After all Christmas is coming!! looks like the SS pin's do a great job. I love nice clean brass.
 
K9 I ordered the tumbler from Harbor Freight tool Co. 3lb. Rotary Rock tumbler $40 tel. # 1-888-866-5797 can check out on line. The Stainless Steel Pins from STM ordered the 2 lb as pin replenisher & lemiShine cleaner, cheaper then ordering 5 lbs of pins can also check them out on line at stainless tumbling media . com I think it was around 15 dollars. Pins never have to be replaced, the 3 lb. Tumbler uses 1 lb. of pins they also carry a 2 3lb tumbler for around $ 52. I have cleaned 40 308 cases in my 3lb. tumbler worked great . STM tel. # 1-801- 810-9850 Hope I Helped. Have a happy & healthy holiday.
 
This Forum is a great help to us loaders... I had been trimming of the flash holes for a long time. But I thought the pockets only needed cleaning. I use to get primers that just would not seat no mater what I would do. crushing primers in to the pockets with a flat to one side then when my Super Black Hawk cylinder would not move because the primer was fouling the frame I figured some thing is wrong and I need to solve the problem. That Redding uniformer was the answer. No more tight primer pockets, no more high primers. It's a simple solution to a old problem. Now about old problems that harbor freight tumbler is on the list. I like every thing I have hird about the process. Also it sounds like I could dump some old equipment (Vibes...). I find that I have ran out of space.
 
Believe me Longshot ,I wish I went with the wet tumbler with SS pins along time ago . I have the dry vibrating unit & three drums that are now sitting on a shelf. The brass comes out with the SS pins I can't wait to foul up the brass again I think I'm getting strange, when you like cleaning as much as shooting. Till the next time .Be Safe Chris
 
I usually just run a brush in them, but when forming different brass, the pocket can get a little tight. Then I skim the pocket. I have never had a missfire in thousands of reloads.
 
Primer pocket uniforming with a cutter can be a good gage of pressures.

In arriving at what each handloader has determined to be safe pressures for cartridges fired in his rifle, there are many signs or indicia of pressure. The well known primer flattening/cratering is but one of them, and as I understand it, if you are seeing these signs, you are already over maximum pressures.

Case head expansion is another one. I buy a box of factory ammo built on the same cases as the ones I intend to reload. I mic the fire ring and jot that number down. Using virgin cases, I will fire those and as they reach the same fire ring number, I know that I am reaching max.

Lastly primer pocket uniforming is helpful in that the brass around the flash hole will tend to bow inwards into the primer pocket more so with higher pressures. Running a simple Lee scraper tool into the pocket initially will give a handloader an indication of how much it has bowed. Follow that with a cutter and get a feel for how much brass is removed will also give you an indication of pressure. (You have to have uniformed the primer pocket of the virgin brass beforehand). -The more brass flakes removed in the uniforming process, the higher your pressures.

Lastly primer pocket uniforming can give the handloader an indication when his brass is worn out. After X number of uniformings, toss it.

These techniques are largely intuitive and comparative rather than quantifiable scientific tests, but I find that they can be helpful.

Sorry to be long winded but perhaps this might help someone.
 
I have no idea what "Uniforming primer pockets" really means. I assume you are going in with a reamer to get a standard diameter. When you re-form some cases into other cases, the head will actually be swaged down. This will somewhat give you what was described in the post above. He is correct that this usually is the sign of a problem. Over swaging the head will make the head diameter smaller instead of bigger and crush the pocket. I was making 6.5 Japanese brass from .303 British brass. The primer pocket of the Remington brass became so tight I was afraid to force a primer in. I reamed the pockets and it was fine. I started using Winchester brass, which generally has smaller dimensions. The thing about reloading is there are really no absolutes. There are just too many variables between the components and the guns.
 
pockets

Thank you Joe for getting to me. I uniformed my primer pockets every time I sized my brass, I changed my brass cleaning from dry tumbeling media, to wet tumbeling with stainless steel pins. The pockets come out spotless.
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Bottom line....do these produce more accurate ammo than if left untouched?

Pete
 
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