I am using the RCBS swager and still reaming to get my .223 primers to seat right . II use my case prep machine to ream and uniform the primer pockets.

I had a similar experience last night installing primers for my first time ever. I am new to reloading and I recently finished the brass prep process on once-fired Lake City 5.56. I removed the military crimp using a Frankford Arsenal Case Prep Center that had a RCBS TM military crimp remover, followed by a primer pocket uniformer, followed by a primer pocket brush. I also checked the primer pocket size using a Ballistic Tools go-no-go gage during this crimp removal process. I then trimmed and ran the brass thru an ultrasonic tank.
I am using Remington 7 1/2 primers and a Forster bench mounted primer seater. Being the first time I have ever seated a primer, I was a little surprised how easily they went in. They are not recessed below flush, they extend out a very slight amount. I only installed primers in ten cases because I wanted to verify everything before proceeding further.
What had me concerned most was someone on YouTube who mentioned he had removed military crimps on Lake City brass, then reloaded them and literally had primers fallout while shooting his AR-15. Evidently his process oversized the hole during crimp removal, I do not remember what primers he installed.
I think I am okay on both the depth of my primer seating and pocket-size, I just like to err on the side of caution.

Catfishmoon, your primers should be flush or below flush — not protruding. Protruding primers can get hit during feeding or loading in the mag and cause the round to go off, or they can be set off when the round is fed into the chamber, perhaps by a free-floating firing pin hitting them too hard.

weird...I simply use a reamer to remove the extra metal from the crimp, after reaming, some are a little tight going in, but they don't get smashed. So far no high primers or mis-fires.

After work last night I measured the cases in which I had installed primers and most did extend out very, very, slightly... When I measured with a caliper, the difference was less than .001 and hard to detect a difference. However, when I drag a straight-edge over the head of the case, I ever so slightly catch the edge of the primer that is not seated below flush.
I will put the cases back into the Forster bench primer and apply a little more pressure and make certain the Forster is adjusted correctly. I also have a few different brands of primers and may try a few of those just to see if I can detect a difference when seating other brands.

I'm reasonably convinced that the Dillon Swager with the long guide rod is the culprit here--it appears to be pushing the primer pocket floor closer to the case head face.

We'll let MadPick get his pocket conditioning tools to see if there is an easy solution to this shit-ton of brass I have that is only marginally useful!

Sounds good. I believe we're also waiting for you to put some cases with "bad" primer pockets into your Swage It and see if it makes them deeper . . . correct?

Hah. Yep. I did that and sadly, it made zero difference. Like I mentioned in the previous test I found that the depth increased by ~ 0.001" but that's probably because the metal is pushed out just a touch at the lip on the case head face.

I sometimes wonder why, if something is working properly then why bring out a dial or a digital caliper...

But it wasn’t working....

Hahaha . . . and yes, that's often correct. In this case though, we were having trouble with priming .223 cases properly.

Madpic said: caliper...


Hahaha . . . and yes, that's often correct. In this case though, we were having trouble with priming .223 cases properly.

Well dang ole Caveman must not have read the whole thread. Ooppsss
To be honest, I’ve never had a problem with priming 223/5.56 cases except when a few slipped by the swaging process. In the beginning I reamed the pockets, I’ve since retired those 3-4 shot cases to the recycle bucket. I’ve used the Dillon SS (already adjusted) and the RCBS swager. Must be something out of spec somewhere but I’ll stay subscribed.
I’ve only loaded thousands but I’ll bet youz guyz have loaded tens-hundreds of thousands.

Well, the tools arrived quickly but it took a while for my lazy ass to try them out.

Here's an example of one of my "bad" pieces of Lake City .223 brass. See how the primer pocket gauge sticks out of the pocket just a little? That means that the pocket is too shallow:



Now if I stick that same piece of brass onto the K&M tool, there's a gap of about that same amount:



And when you fire that sucker up, here's what it looks like:


https://www.youtube.com/watch?v=kDZ48B56fp4

The K&M tool is set to a depth of 0.122"; recall from earlier in the thread that a small primer pocket should be 0.117-0.123" deep. I did maybe 50 cases, and it removed material from all of them. The example in the pics and video above was among the worst of the bunch.

Interesting, well now I feel bettet about uniforming my primer pockets with the little lyman hand crank. You can see where it takes some material off the case.

Reaming is not the way this should be done.

I’ve been using a rcbs swager die for everything for 5 plus years with no problems

No go gage
Tight primers
Never flush , always below

I use a hand primer or press, depending what I’m doing. You can feel the difference in a seated or a “maybe” one, then just run it again.