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I see it written alot about primer pockets getting loose, what causes this, and how do i avoid it? I havn't been loading too long but the 4 cartridges that I load for the .308w, 45/70 and .444 have been loaded 5 times each or more, and the Hornet already on its 4th loading this week. Can't learn if you don't ask. .DT
 

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I've always used a primer pocket uniformer (squares the flat portion of the pocket) and have yet to have one wear out (get loose) now then, I have had brass split, head seperation etc. but never had the primer pocket get loose, I'm sure it would happen eventualy, but the brass always wore out first. some of my brass is on its 10th loading! (T-4, and 40-65win)
 

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"I see it written alot about primer pockets getting loose, what causes this, and how do i avoid it?"

Avoid loose primer pockets by not loading so hot you swell the case heads. Pockets that get so loose in 4-6 firings that we can seat new primers with our thumb is the surest sign of moderately excessive pressure.

Head seperations are a sign of repeated excessive shoulder set back during FL sizing, neck/body splits occur from metal fatigue after too many reloads; neither are signs of excess pressure.
 

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Fuzzball hit it out of the park -- outstanding answer. What he says -- +1 for me.
 

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Lost nearly 70 very nice/expensive Lapua .308 Win cases after ONE firing because I was using a near max temp-sensitive powder on a warm/hot day with the strong sunshine beating down on me, my rifle and the ammo.

These were long-range competition loads, so velocity was important, right up there with accuracy. Shot a good score during the match that day, but when I tried to reload that brass, the new primers would just fall out. That was a lesson learned right there.

Switched back to Hodgdon's Varget, and never had a primer-pocket problem again, even with max and near max level loads.

Regards, Guy
 

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1 big hole said:
I've always used a primer pocket uniformer (squares the flat portion of the pocket) and have yet to have one wear out (get loose) now then, I have had brass split, head seperation etc. but never had the primer pocket get loose, I'm sure it would happen eventualy, but the brass always wore out first. some of my brass is on its 10th loading! (T-4, and 40-65win)
Not meaning to highjack the thread but which uniformer tool do you use? I've been looking to replace my finger operated Sinclair with something not so hard on my old hands. Do you know of any power operated uniformer? I agree that uniform primer pockets yield many benefits. TIA, ph
 

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ph said:
Not meaning to highjack the thread but which uniformer tool do you use? I've been looking to replace my finger operated Sinclair with something not so hard on my old hands. Do you know of any power operated uniformer? I agree that uniform primer pockets yield many benefits. TIA, ph
I use the RCBS Trim mate. You can mount the primer pocket uniforming bit onto the machine and go at it. You will probably have to get the RCBS bit to go on the machine. You can do quite a few rounds before your fingers get sore. I just finished off doing 200 rounds of new factory Winchester .257 Robt. brass. I trimmed all the brass to the "trim to" length, reamed out the flash holes and uniformed the primer pockets. I dunno if anyone else makes a power tool for the job but that's what I use and it works. I guess you just have to decide if you want to spend that much money as the tool ain't cheap. :( I felt it was worth it and it does make chamfering a less onerous job. ;)
Paul B.
 

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they all are about the same...(and do a good job!) but I'm useing "Lyman" at this time, had an old K&S for many years but became MIA, the "Lyman" was/is the replacement. Just a side-note, I've never used one in a trimmer stand, always by hand in front of the TV.
 

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I have some 45ACP brass I have thrown out. The primer pockets were loose... but I've probably fired them well over 20 times each.


On primer pocket uniforming tools, I use the redding tool in a drill. Works wonders. ;D
 

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High pressure can do it, as said. I only uniform primer pockets on cases used in rifles accurate enough to benefit from it. Uniforming pockets can also ream out too much metal on the sides and casue loose pockets prematurely, so caution is required.
 

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preacher said:
High pressure can do it, as said. I only uniform primer pockets on cases used in rifles accurate enough to benefit from it. Uniforming pockets can also ream out too much metal on the sides and casue loose pockets prematurely, so caution is required.
+1


I want to say to those who own 6.5x55 swedes. Norma brass has unusually shallow and tight primer pockets, reaming them out will be necessary.
 

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I have loaded 9mm and 45 acp cases enough times that primers started getting loose, but those cases had to be loaded 40-50 times. I've got 38 special cases that I've been loading for 20 years or more. I figure when the pockets get loose it's time to spring for new brass. The thin wall tapered cases used in lever guns seem to separate case heads more often than anything else, 30-30, 25-35, 32 special, 32-20, 218 bee. I usually check them inside with a feeler and scrap the batch when they develop an annular ring inside.
 
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