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primers won't seat completely on lake city 7.62

I recently bought some once fired lake city 7.62 brass. I swaged the primer pockets (I even chamfered them a little), then I used a Sinclair primer pocket uniformer on a power drill for about 10 seconds. The primers will not seat completely on most cases. Thanks for any help.
 
Well, if a Sinclair uniforming tool was used on the cases then it sounds like to me there is something not working right on the primer seating tool you are using. The pocket can only be reamed so deep and the Sinclair is a fixed tool so unless it is not cutting properly, 10 seconds worth should put that primer pocket right.
That said, LC brass typically has a strange radius in what should be the bottom corner of the pocket. This has to be removed for an aftermarket or reloaded primer to have room to go in and seat correctly. But, as stated, the Sinclair is excellent at doing just that.
You should be able to feel when the uniformer "unloads" and quits cutting. At this point there is nothing left to do with the primer pocket. Sinclair uniformers cut fast and have a good feel to them when being used.
If by chance you are using a Lee priming tool to do the seating I have found that, being made out of pot metal, the "cam" that pushes the primer ram gets worn fairly quickly and ceases to seat the primer deep enough. Best way to confirm that the case and/or pocket is correct is to seat one with a Lee Ram Prime. If that don't send it to the bottom of the pocket I don't know what to tell you to check next...had an old guy who's hands were falling asleep once, doubt that is your problem though.
 
Are you using Winchester primers? How far are the primers protruding above the case head? google: rifle primer chart. It goes like this, Win.= .121", Rem. = .119", CCI =.118", fed. =.117" cup depth. A primer switch might solve your issue . If it does, run the uniformer one more time after firing to insure you have a uniform depth. I learned this the hard way with some shallow pocket Norma brass. What felt like the uniformer "bottoming out" wasn't really true. K&M uniformer..... not the uniformers fault but mine:(............ Keep the case heads clean the smallest piece of grit between case head & uniformer will yield s shallow pocket.
 
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Are you using Winchester primers? How far are the primers protruding above the case head? google: rifle primer chart. It goes like this, Win.= .121", Rem. = .119", CCI =.118", fed. =.117" cup depth. A primer switch might solve your issue . If it does, run the uniformer one more time after firing to insure you have a uniform depth. I learned this the hard way with some shallow pocket Norma brass.
I've tried Win,Rem, & Fed primers all with the same result. They protrude about .010-.025".
 
Well, if a Sinclair uniforming tool was used on the cases then it sounds like to me there is something not working right on the primer seating tool you are using. The pocket can only be reamed so deep and the Sinclair is a fixed tool so unless it is not cutting properly, 10 seconds worth should put that primer pocket right.
That said, LC brass typically has a strange radius in what should be the bottom corner of the pocket. This has to be removed for an aftermarket or reloaded primer to have room to go in and seat correctly. But, as stated, the Sinclair is excellent at doing just that.
You should be able to feel when the uniformer "unloads" and quits cutting. At this point there is nothing left to do with the primer pocket. Sinclair uniformers cut fast and have a good feel to them when being used.
If by chance you are using a Lee priming tool to do the seating I have found that, being made out of pot metal, the "cam" that pushes the primer ram gets worn fairly quickly and ceases to seat the primer deep enough. Best way to confirm that the case and/or pocket is correct is to seat one with a Lee Ram Prime. If that don't send it to the bottom of the pocket I don't know what to tell you to check next...had an old guy who's hands were falling asleep once, doubt that is your problem though.
I use my rock chucker press to seat the primers. Yes, I do feel the uniformer unload.
 
They protrude about .010-.025".
That's a HUGE amount of protrusion. There's something else going on here. :oops::oops::confused::confused:............. Are the bottom of the primer pockets square or do they have a "step" in them?? Can you give us a Pic?
 
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If the primer pocket uniformer is adjustable it might be out of adjustment.

The pistol and rifle depths are different. You might be using a pistol tool on rifle primer pockets.
 
Large rifle depth should be between 0.125" to .132" small rifle between .117 to .123" this is Saami spec( in case you're using a small rifle reamer by mistake)............ Use the bayonet end of your caliper and take measurements. You can have up to .008" of depth from top of primer to case head and still be in spec (SAAMI)............. Though .003" to .006" would be ideal ........................ measure case length, measure pocket depth, measure primer thickness then measure case with primer seated for your answer. Note: the bottom of your primer pocket must be perfectly flat for these measurements to be accurate.
 
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By chance are you using a shell holder that is a brand other than RCBS???? I would suggest you take the priming tool you are using apart and give it a good cleaning...as gotcha suggests, a little dirt or grit can go a long ways in fouling things up. There is just not a lot to this operation to be too terribly wrong. I believe when you tear down that priming attachment you will find something. Look for a burr or other defect around that thin little cylinder {for lack of a better term} that holds the primer while you press it in. make sure everything moves easy by hand with no primer and then try it all with a primer.
As far as I know Sinclair doesn't currently make an adjustable uniforming tool...they may have in the past though, just as several others, RCBS included do now.
This is a dumb question, but are you applying enough pressure to seat the primer??? What happens if you give more??? Is it locking up solid and leaving .025" hanging out??? That is a lot. The very last little bit requires a little more pressure, you are seating the anvil too.

Edit: Unless this is LC LR brass somebody might have swaged the primer pocket to get rid of the primer crimp...if so and the ram was set too long it will also move the brass inside the case just as suggested with a decapping rod of a size die. Did you swage out a crimp or get the brass already swaged??? I have only ever seen the Lake City LR brass come from the factory not crimped...all the rest is crimped and would have to be removed.

Double edit: Just went back and read your post again, I see you swaged them. Are you certain that the sawger was set correctly??? There is a fine line between getting rid of the crimp and mashing the brass case. Still, it seems like to me the uniforming tool would cut the excess swaged case away and let the primer seat. Might not be right, might leave the case too thin inside, but it should give you the correct depth for the primer to seat.
 
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Large rifle depth should be between 0.125" to .132" small rifle between .117 to .123" this is Saami spec( in case you're using a small rifle reamer by mistake)............ Use the bayonet end of your caliper and take measurements. You can have up to .008" of depth from top of primer to case head and still be in spec (SAAMI)............. Though .003" to .006" would be ideal ........................ measure case length, measure pocket depth, measure primer thickness then measure case with primer seated for your answer. Note: the bottom of your primer pocket must be perfectly flat for these measurements to be accurate.
My primer pockets are consistently .132" after using a Sinclair uniformer. I've been reloading for almost 40 years and this is my first experience with military 7.62 brass. I've used military 5.56 brass with absolutely no trouble at all. I am really confused with this seating problem. Has anyone else had this problem? Or am I overlooking something that is so obvious that I can't see it? Is it possible to special order a primer pocket uniformer with a .142 (or more) depth?
 
I have personally loaded and shot tens of thousands of 7.62X51 that was crimped. Never had an issue with the brass cases and seating primers. Did have an issue with those little Lee primer tools though, as I said before they will wear out quick if you use them dry. The one I had that did it really didn't owe me anything...it probably primed 10-12 thousand cases before it puked and Lee sent me a new cam.
I load all of my 243, 260, 7mm-08 and 308 with former once fired, usually lake City brass...I prefer the LR stuff when I can get it, but my nephew is no longer at Quantico, so those days of all the free LR I can stand are over.
it has to be something stupid...probably not jumping right out at you, but when you find it it will be something stupid.
 
I had the same problem with my rock chucker press loading 221 fireball went thru everything you have described,i was using Rem 71/2 tried several different brand of primers and had the same problem tried the cci 450 and worked perfectly have not figured out the problem yet but did have the deprime rod set to long for some of the cases. used them up for PD,s and have not went back to them yet
 
I have personally loaded and shot tens of thousands of 7.62X51 that was crimped. Never had an issue with the brass cases and seating primers. Did have an issue with those little Lee primer tools though, as I said before they will wear out quick if you use them dry. The one I had that did it really didn't owe me anything...it probably primed 10-12 thousand cases before it puked and Lee sent me a new cam.
I load all of my 243, 260, 7mm-08 and 308 with former once fired, usually lake City brass...I prefer the LR stuff when I can get it, but my nephew is no longer at Quantico, so those days of all the free LR I can stand are over.
it has to be something stupid...probably not jumping right out at you, but when you find it it will be something stupid.
Tomorrow I will clean my primer assembly & see how that goes. It has to be something obvious. (I hope!) I am overwhelmed by all the responses from you people. You guys are awesome! Thank you for all the help!
 
Well, if a Sinclair uniforming tool was used on the cases then it sounds like to me there is something not working right on the primer seating tool you are using. The pocket can only be reamed so deep and the Sinclair is a fixed tool so unless it is not cutting properly, 10 seconds worth should put that primer pocket right.
That said, LC brass typically has a strange radius in what should be the bottom corner of the pocket. This has to be removed for an aftermarket or reloaded primer to have room to go in and seat correctly. But, as stated, the Sinclair is excellent at doing just that.
You should be able to feel when the uniformer "unloads" and quits cutting. At this point there is nothing left to do with the primer pocket. Sinclair uniformers cut fast and have a good feel to them when being used.
If by chance you are using a Lee priming tool to do the seating I have found that, being made out of pot metal, the "cam" that pushes the primer ram gets worn fairly quickly and ceases to seat the primer deep enough. Best way to confirm that the case and/or pocket is correct is to seat one with a Lee Ram Prime. If that don't send it to the bottom of the pocket I don't know what to tell you to check next...had an old guy who's hands were falling asleep once, doubt that is your problem though.

Same problem with a 40 YO Lee priming tool. Unscrew the shell holder and look at it inside. The cam is soft aluminum. Put a light coat of grease on it. I had a second seldom used Lee tool set up for large primers. Swapped parts works OK now. With a caliper measure how far the push pin comes up. Compare it to a tool that works or go thru the math. Uniforming the pockets would give the proper depth. The diameter of the pocket should be OK, since the primer goes in most of the way. I would think the primer tool wouldn't be off by 10 thou., but that's what it sounds like.
 
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My primer pockets are consistently .132" after using a Sinclair uniformer. I've been reloading for almost 40 years and this is my first experience with military 7.62 brass. I've used military 5.56 brass with absolutely no trouble at all. I am really confused with this seating problem. Has anyone else had this problem? Or am I overlooking something that is so obvious that I can't see it? Is it possible to special order a primer pocket uniformer with a .142 (or more) depth?
STOP !!! your primer pockets are already at SAAMI max depth as per my info above. Suggestion: seat a SPENT primer into one of your cases using your Rock Chucker priming attachment. Then use a small rod, maybe a nail cut flat on the end and gently try to tap the SPENT primer deeper into the pocket. If it (the primer) goes deeper you've identified your problem.( the priming arm) If it doesn't the problem would be caused by some part of your prep IE chamfering, swaging............ Or borrow a hand priming tool from a friend and see if the hand tool fully seats the primer.

























0 Suggestions: Seat a SPENT primer into a case using your Rock Chucker priming arm.
 
You said this is the first time you have used NATO brass. If you have commercial 308 brass, are they seating properly? Compare the measurements of the commercial brass with the uniformed NATO brass and see where the difference lies.
 

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