Primers barely not seated fully. Will they fire?

[joejoe05]

I have some 9mm reloads that wobble ever so slightly when I put them up against my calipers. You can’t visually tell that the primers are sticking out; they look flat and even feel flat against the finger.

If the protrusion is very slight, will most of them fire without issue? I’m just shooting at paper targets 15-25 yards away. Has anyone been in a similar situation and tried firing them?

CCI 500 primers in FC casings from a Dillon XL750.


Also, I adjusted from reloading sitting in a chair to standing up and no longer see the issue in my new loads.

[Long Branch Setter]

Be very careful. Dropping the slide could cause a “slam” fire.

LBS

[Wobbly]

The problem is that they probably won't chamber in your gun, because it disrupts the head spacing. And you certainly don't want the slide slamming down on the primer (which is the highest part) and setting it off. That's the whole point of having them below flush.

What you can do is run them back though the press at the primer seating station. It's not optimal, but it can be done. I want you to slip it in station #2, then (with your safety glasses on) you can stand on the opposite side of the press structure so that you can't see the cartridge, then apply very slow, steady pressure to fully seat the primer.

It will be OK.

[George16]

Have you checked your primer assembly and make sure it’s setup properly? The xl750 like the 550 enables you to adjust the primer punch and cup assembly to make sure you seat the primers to its proper depth unless the case is crimped. It should be set between 1.376-1.385”. You can find the settings on page 59 of your manual.

[lewmed]

 You might try adjusting your shell plate if it is too loose the shell plate will tilt when seating a primer. I noticed on my XL 750 when running mixed brass 90% of my high primers were in Remington brass they must have tighter pockets. After I adjusted the shell plate the issue went away I just finished a batch of 3800 rounds of 124gr jhp and I only found 5 or 6 high primers.

[joejoe05]

I had my shell plate tightened but did not know about the primer assembly adjustment. I played around with it and have my primers seating even better now. Thanks.

[George16]

I had my shell plate tightened but did not know about the primer assembly adjustment. I played around with it and have my primers seating even better now. Thanks.

Glad it’s all working good for you now.

[Wobbly]

I guess that's our primer on primers.   

[larryflew]

If just slightly short of seating you will likely have some that don't fire if they do chamber. Pull the trigger again as the first time sets the primer for you and second time will likely fire. LONG time ago I had a small batch like that and used them on a steel shoot. Needless to say my times where at the bottom of the competition but all fired on the 2nd pull. Too bad it took me so long to discover the problem as I chucked a lot of them out by hand before realizing what the problem actually was.

Since then my inspections have evolved, live and learn I guess.

[joejoe05]

I was able to shoot my reloads yesterday and had zero failures. I probably had over 200 rounds with primers that were flush or very slightly protruding. Again, they looked flat, but had a slight wobble when put up against my calipers. These were CCI 500 primers in 9mm FC casings, shot on a CZ custom shadow target (11lb recoil spring and 13lb main spring).

I read that .002 -.005 is the ideal seating depth for the CCI primers, but it looks like flush or even very slightly out can at least be functional. Not something I'm recommending but just sharing my real world results.


BTW, I have primers seating below flush consistently in my newer loads and will always try to stay within recommended specs.

[Wobbly]

Primer seating is "an acquired taste".

Looks like your acquiring quite well. 

[SI VIS PACEM PARRABELLUM]

If you make sure your press is mounted rigidly so there's no deflection when you reach the priming stroke and make sure you push the handle fully forward during that stroke you should see your primers seating nicely.

[Wobbly]

You might try adjusting your shell plate if it is too loose the shell plate will tilt when seating a primer. I noticed on my XL 750 when running mixed brass 90% of my high primers were in Remington brass they must have tighter pockets.

Instead of tightening the shellplate center bolt by screwing it down, the system I prefer is to run the bolt all the way down until all the slack is taken out and where the shellplate can't move, then loosening the bolt a tiny amount until the shellplate can barely move.

[ericsl2]

If the primer is just ever so slightly raised the way it is in your case...can't see but can feel, it's not going to hurt anything. When is obviously protruding slam fire is the worst outcome. Fail to fire on the first try is pretty likely