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Primer seating depth

I understand your problem, unfortunately I have older military information (from the 1980s) that includes recommended depths for Olin and Remington products, all of them recommended a seating depth (from the base of the case to the top of the primer cup) of .002" to .006". I personally seat mine to around .004" plus or minus a couple thousandths since it's not possible to seat every primer exactly the same. I use a pocket uniformer in order to get as consistent seating depth as possible and I use it every time I reload a case so that there is no carbon build up. Unfortunately I suspect that foreign brands of primers may not conform to this standard so it without data I'd say that you would have to experiment before you could find some reliable seating depth. Regardless, I don't recommend seating flush nor do I recommend seating until you deform the cup.
 
First you must have a priming tool solid enough to feel the anvils touch then you show them with calipers just how much .005 is and tell em to push it that much farther. Its hard to teach a feel but you can tell them what to feel for

When I started reloading 10+ years ago, I bought a Sinclair hand priming tool. (now have 2). It was really obvious for someone who knew absolutely nothing about primer depth to confidently "feel" when the primer hit the "bottom" of the pocket. Boy, it was easy. Primer case looked to be about .003 -.005" or so ? beneath the rim. I did & do uniform pockets w a Sinclair tool. This seems to be OK & I haven't thought about it since. Of course I don't shoot BR or at 1000 yds either...
pic for reference, not claiming to be a primer guru. fwiw. it's at the bottom.
I now think it's about .008" or so. works.
BR-2a Primer.jpg
 
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When I started reloading 10+ years ago, I bought a Sinclair hand priming tool. (now have 2). It was really obvious for someone who knew absolutely nothing about primer depth to confidently "feel" when the primer hit the "bottom" of the pocket. Boy, it was easy. Primer case looked to be about .003 -.005" or so ? beneath the rim. I did & do uniform pockets w a Sinclair tool. This seems to be OK & I haven't thought about it since. Of course I don't shoot BR or at 1000 yds either...

if you want to take that to the next level you can get the 21st century super precision one and dial in a solid stop. the sinclair one is solid enough you can feel everything. I used one for PPC for like 18yrs and finally had to replace the hinge pin. best priming tool ever made i'd say.
 
Which is actually my point, you can't teach proper primer seating without some kind of dimensional data, you can't just tell a novice to simply press a primer in to the pocket until the anvil seats, they don't have any idea how that feels and with a press you wont even be able to feel the anvil seat. If you do some research you'll find that all primer manufacturers recommend that the primer cup be seated to at least .002" below flush and most use a range of depths of .002" to .004" with some recommending as deep as .008". The cup must be below flush in order to set the anvil at it's proper place, too shallow and the primers can be insensitive due to not enough energy being transferred to the mix, too deep and the primers can be insensitive due to the mix being crushed and pushed away from the anvil/cup contact area.

IMO you are trying to make something that is very simple complicated. Somehow everyone that I know managed to feel when the primer bottomed in the pocket without any dimensional data at all. If one has feeling in one's hands and is using a hand priming tool it is about as difficult as determining that the sun is shining at noon on a cloudless day. In the distant past when I was much less sophisticated I actually ruined the main casting of a RCBS hand priming tool, the kind that took regular shell holders, by getting too carried away with seating force putting way too much "preload" on primers after I felt them bottom. After all, if some is good, isn't more better ;-) In any case, I never had any problems related to primers during that time. These days, my grip is less gorilla like, and I have developed a more subtle and well reasoned approach, so I only put a little extra squeeze on the priming tool after I feel the primer bottom. Still no problems whatsoever. We do not need to have map coordinates to mow the lawn. Seating primers by feel is less complicated than tying one's shoes, yet some feel the need for complexity. Good luck with that. Back when I taught a little math, I would explain the new material as if it was really no big deal, and when I had finished an explanation that was simple by design, I would tell the students that that was all there was too it, and ask them if they wanted me to make it more complicated. Of course the resounding answer was NO.
 
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Amen! My first priming effort was with an old Lee Loader. I pounded them in with a 2x4 to just a "leetle" below flush, just like the factory ammo. As crude as they were, those reloads outshot my factory loads. When I procured a Lee Autoprime, I considered it a miraculous device. I'm not sure the past 40 years have brought very much progress on the priming front. JMHO
 
Amen! My first priming effort was with an old Lee Loader. I pounded them in with a 2x4 to just a "leetle" below flush, just like the factory ammo. As crude as they were, those reloads outshot my factory loads. When I procured a Lee Autoprime, I considered it a miraculous device. I'm not sure the past 40 years have brought very much progress on the priming front. JMHO
Amen! I love my older Lee AutoPrime (round tray) so much, I bought a backup while I still could when I saw they had "improved" it, God knows how or why - I don't want to know. Then sure enough I started reading complaints about the new version. (Since I eschew Federal primers, I just ignored the curious warnings about those in the old Lee.)
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IMO you are trying to make something that is very simple complicated. Somehow everyone that I know managed to feel when the primer bottomed in the pocket without any dimensional data at all. If one has feeling in one's hands and is using a hand priming tool it is about as difficult as determining that the sun is shining at noon on a cloudless day. In the distant past when I was much less sophisticated I actually ruined the main casting of a RCBS hand priming tool, the kind that took regular shell holders, by getting too carried away with seating force putting way too much "preload" on primers after I felt them bottom. After all, if some is good, isn't more better ;-) In any case, I never had any problems related to primers during that time. These days, my grip is less gorilla like, and I have developed a more subtle and well reasoned approach, so I only put a little extra squeeze on the priming tool after I feel the primer bottom. Still no problems whatsoever. We do not need to have map coordinates to mow the lawn. Seating primers by feel is less complicated than tying one's shoes, yet some feel the need for complexity. Good luck with that. Back when I taught a little math, I would explain the new material as if it was really no big deal, and when I had finished an explanation that was simple by design, I would tell the students that that was all there was too it, and ask them if they wanted me to make it more complicated. Of course the resounding answer was NO.

I'm not trying to make anything complicated, you are simply steadfast in your opinion and refuse to acknowledge that factual information from the manufacturers is undeniable. Do I measure my primer depths? In the beginning I did but like you, over time I got the feel for seating the primer without having to measure, but that doesn't help a new guy at all. A novice needs to have some system to guide him while he learns, you can't just say you'll feel the anvil seat, I've tried to teach people that technique and until they set a few primers using a depth measurement they simply did not feel the anvil seat itself. Sometimes it's a matter of making them slow down and press the primer in to the pocket slowly but others needed more guidance, that's a reality, not everybody picks up on these techniques like you or others do.
 
I'm not trying to make anything complicated, you are simply steadfast in your opinion and refuse to acknowledge that factual information from the manufacturers is undeniable. Do I measure my primer depths? In the beginning I did but like you, over time I got the feel for seating the primer without having to measure, but that doesn't help a new guy at all. A novice needs to have some system to guide him while he learns, you can't just say you'll feel the anvil seat, I've tried to teach people that technique and until they set a few primers using a depth measurement they simply did not feel the anvil seat itself. Sometimes it's a matter of making them slow down and press the primer in to the pocket slowly but others needed more guidance, that's a reality, not everybody picks up on these techniques like you or others do.
I guess my point was that as long as you seat primers, by hand, to the point where you feel resistance, you should be OK. I think anyone can feel the point where going any farther would require a lot more effort. People who are at that basic stage of reloading should not concern themselves with a lot of stuff that some more experienced loader like to discuss. As the other fellow mentioned about his experience, I too started loading with a Lee Loader, and in my case a plastic headed mallet. None of that ammo, that I tapped the primers into had any ignition issues. From time to time I have met fellows who after some discussion I told that for their purposes, they did not need to reload. What was really going on was that I had made a determination that they were going to be resistant to learning, because they tended to throw up road blocks at every opportunity, so it was simpler to just pat them on the head (so to speak) and change the subject. Generally, if a person is really interested in a subject, and really wants to learn about it, he will.
 
So... I'll throw this out there, and see what the brain trust has to say ;)

I've got some 1x fired Norma brass that has been proving to be exceptionally difficult to prime. Even when the primer pockets have been cleaned and uniformed... the primers won't seat flush, much less below flush, without visibly mashing the primers like those shown in post #82.

Never had this problem before, even with virgin Lapua brass. Open to suggestions.
 
does the top of the pocket have a radius ?
what did you use to uniform the pockets ?
what are you priming with ?
what primer ?
So... I'll throw this out there, and see what the brain trust has to say ;)

I've got some 1x fired Norma brass that has been proving to be exceptionally difficult to prime. Even when the primer pockets have been cleaned and uniformed... the primers won't seat flush, much less below flush, without visibly mashing the primers like those shown in post #82.

Never had this problem before, even with virgin Lapua brass. Open to suggestions.
 
does the top of the pocket have a radius?
Not after being uniformed.

what did you use to uniform the pockets?
RCBS Case Prep center, with the included large primer tool.

what are you priming with ?
Tried doing it on press (550). Ended up having to finish off with RCBS hand priming tool, as I couldn't get them even close to flush with the 550.

what primer ?
Rem 9.5

Exact same setup I've used for thousands upon thousands of Winchester and Lapua cases, with a variety of primers - including Remington.
 
I feel certain we're trying to say the same thing except i'm asking which lot of which brand primer needs to be set at .008"? which lot needs to be set at .004"? measuring primer depth and saying thats the end all is like setting a bullet by a comparator and always putting it there.
No primer needs be seated at .008" or .004". They all only need to be seated somewhat below the base (i.e. recessed), optimally with the anvil contacting the bottom of the primer pocket.
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you need to consider a hornady crimp removing tool to PUT A RADIUS BACK ON THE MOUTH OF THE POCKET. i do not understand how a uniform tool is removing the entry radius.

the prep center does not have a uniforming tool, it has a primer pocket cleaner, and a crimp removing tool, which should leave a radius on the mouth, but maybe not.

sounds like the brass is not really uniformed,
it may just have shallow pockets
look at the sinclair tool for pocket depth and the hornady tool for an entry radius.

Not after being uniformed.


RCBS Case Prep center, with the included large primer tool.


Tried doing it on press (550). Ended up having to finish off with RCBS hand priming tool, as I couldn't get them even close to flush with the 550.


Rem 9.5

Exact same setup I've used for thousands upon thousands of Winchester and Lapua cases, with a variety of primers - including Remington.
 
on the 550,
if the shell plate is adjusted loose, it will hold cases high and keep the priming tool from seating the primer.

Tried doing it on press (550). Ended up having to finish off with RCBS hand priming tool, as I couldn't get them even close to flush with the 550.
 
you need to consider a hornady crimp removing tool to PUT A RADIUS BACK ON THE MOUTH OF THE POCKET. i do not understand how a uniform tool is removing the entry radius.

Okay, I think we're getting a little off track here. I meant the uniformer is cutting / squaring the *bottom* of the pocket. I don't have *any* tools that touch the mouth of the pocket.

the prep center does not have a uniforming tool, it has a primer pocket cleaner,
Which historically does a pretty damn fine job of cutting the bottom of the primer pocket.

and a crimp removing tool, which should leave a radius on the mouth, but maybe not.
Mine did not, to the best of my recollection, come with such a cutter. At one point in the distant past I had a *Hornady* cutter like that for SR pockets, back when I had nothing better to do with my time than try to rehabilitate mil-surp LC 5.56 brass. Those days are *long* gone.

look at the sinclair tool for pocket depth
If I have to dust off *that* thing, I may just go get new brass.

on the 550,
if the shell plate is adjusted loose, it will hold cases high and keep the priming tool from seating the primer.

Not my first rodeo. The 550 is adjusted correctly, including the shell plate.

As I said, even a hand priming tool cannot seat the primers to flush, without *mashing* them and leaving visible marks from the seater.
 
As long as the primer bottoms out in primer pocket your good to go, doing it by feel with a hand primer is very easy to pick up a feel for... to the non believers just try it for yourself and you’ll get a feel for it pretty quick, it’s not a complicated procedure by any means..

Cheers Rushty
 
On the question about the Norma brass, and not being able to seat primers properly, years back, when I was first loading for 6PPC using Lapua .220 Russian brass, there was a known problem with those cases having too big of a radius at the bottom corner of the pocket. Russ Haydon sold a special tool for removing just a little material to fix that. It was a fixed depth carbide tool that was slightly smaller in diameter than my "normal" uniformer which, having no provision for cutting the sides of a pocket, would tend to get wedged in when I tired to use it on those cases to fix that problem. The tool worked very well, but I have not needed it for a long time probably because Lapua fixed the problem.
 
On the question about the Norma brass, and not being able to seat primers properly, years back, when I was first loading for 6PPC using Lapua .220 Russian brass, there was a known problem with those cases having too big of a radius at the bottom corner of the pocket. Russ Haydon sold a special tool for removing just a little material to fix that. It was a fixed depth carbide tool that was slightly smaller in diameter than my "normal" uniformer which, having no provision for cutting the sides of a pocket, would tend to get wedged in when I tired to use it on those cases to fix that problem. The tool worked very well, but I have not needed it for a long time probably because Lapua fixed the problem.

Too bad Russ closed up shop. It was awful nice being able to call them up, and have all kinds of precision loading goodies here pretty much the next day (other side of the mountains).

At any rate, I think I found the problem... and the solution. Primer pockets are within their nominal spec, if a tad on the shallow side. The primers are within their nominal specs, if a bit on the *tall* side. Combined... results in the odd primer that sticks out 5 thou, and the 550 just wasn't able to push them any deeper (or flatter). The cutter on my case prep center may be a bit dull (it's done more than a few cases over the years)... I dug out my Sinclair carbide primer pocket uniformer and it's able to cut the pocket to where the primers seat just flush... or with a little technique on the cutter, a bit below.

I've got 100 pcs of Norma to knock out today... then another 500 pcs of Prime to chip away at over the next however long. Not really looking forward to it :(
 
Okay, I think we're getting a little off track here. I meant the uniformer is cutting / squaring the *bottom* of the pocket. I don't have *any* tools that touch the mouth of the pocket.


Which historically does a pretty damn fine job of cutting the bottom of the primer pocket.


Mine did not, to the best of my recollection, come with such a cutter. At one point in the distant past I had a *Hornady* cutter like that for SR pockets, back when I had nothing better to do with my time than try to rehabilitate mil-surp LC 5.56 brass. Those days are *long* gone.


If I have to dust off *that* thing, I may just go get new brass.



Not my first rodeo. The 550 is adjusted correctly, including the shell plate.

As I said, even a hand priming tool cannot seat the primers to flush, without *mashing* them and leaving visible marks from the seater.

You obviously do not understand the difference between a crimp remover and a primer pocket uniformer. Primer pocket cleaners are not the same thing. If you were refurbishing military cases then you were cutting the crimp out of the pocket. I primer pocket uniformer cuts only the bottom of the primer pocket, it ensures that the pocket is within SAAMI specs and it removes the radius between the bottom of the pocket and the walls.
 
Actually, I do. Someone else jumped into that path over a simple misunderstanding about where the corners were getting squared up at.

Similarly I never said I was trying to ream out a crimp... Pretty sure I explicitly stated "1x fired *Norma*" brass... if you'd actually follow the whole (sub) conversation before making assumptions about what I may or may not understand.

Just sayin'...
 

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