Popped a primer while seating

[15Tango]

I was seating some Remington SP primers into Federal brass. The pockets on these cases were crimped, I cut them out using a 45 degree chamfer. I've always done the same with LC 223 brass and never had an issue. It still caught on a little edge somewhere while seating and needed additional force to get it to go, this happened a few times with these cases so I didn't think anything of it. Once it got past that I squeezed it in the rest of the way and it went off.

I was using my RCBS hand primer which needs to be held at a 45 degree angle to get the primers to flow down towards the little funnel so it wasn't aimed directly at my face but pretty close. I've seated tens of thousands of primers and used the normal amount of force.

I popped the primer back out using a decapping die to inspect what happened but I'm not seeing anything obvious. The primer has a dimple on it going outward, the opposite of what we're used to seeing, from the decapping pin - I think it was able to push it outward because the primer wasn't dented inward like normal.

No harm was really done but, it just startled me and it smelled a lot lie CS gas, it also scared the cat quite a bit. Anyway, I can't see where I went wrong and I'm not seeing anything obvious here - maybe somebody else will.

Wayne

 

[Mark Walker in TX]

I had one go off before as well, but I was not using brass that had ever been crimped. Scared me pretty good, and now when I prime, the dog leaves the loading room.... (Same tool, RCBS hand priming tool)

Its also a very good reminder to always wear eye protection when loading!!

 

[spclark]

Whoo, I've never had a primer pop when seating, but there's ALWAYS a first time I guess!

That's why I NEVER have a case pointed anywhere near my face (or propellant storage rack ) when I'm running my Sinclair one-at-a-time device.

 

[Kenny474]

When it hung up on the lip, the anvil was likely pre-loaded into the priming pellet and may have been pushed into the priming pellet farther than normal or even raised a spot on the back of the primer. If it had raised a spot on the back of the primer when it initially hung up, seating it flush would be enough pressure to crush the priming pellet between the anvil and primer cup and cause it to detonate. If the anvil was somehow different than normal it could easily cause this to happen.

Even if it was only dimpled outward after, it may have just been flattened when you gave the last push to seat it fully.

Just glad you're OK.

Kenny

 

[CaptainMal]

Ouch. Glad you did not get hurt.

Decades of reloading and I never did that. Always wondered what whould happen if it did.
Thanks for the post. Educational.

 

[TheOtherZilla]

Never had one go off while priming or reloading in general. Any crimped cases I have are swagged first.. And yes I conciously keep the business end of the brass pointed away from my face while priming. RCBS tool here as well, but for many years I used a Lee tool..

 

[jonbearman]

I cut the crimp out and doesnt seem to hurt a thing.I use an rcbs chamfer tool in a drill and literally cut the crimp and that is it .Some go in a little stiff but not enough to set it off.Glad you are uninjured,did you get your ears to quit ringing yet?Wayne try my process,it is what most of the commercial reloaders do.

 

[15Tango]

Jon,

Your process is exactly what I do - the RCBS chamfer tool manages to get held by the smaller chuck of one of my drills and it works awesome. It works great and I've never had an issue until now. Maybe it was a fluke.

Wayne

 

[243Mendoza]

I swage all .223 military brass with the Dillon swage tool.

 

[BoydAllen]

Back in the day, I got started reloading with a .308, and would cut the crimp out of primer pockets with the tip of the blade of a large folding knife. The rest of the process was done with a Lee Loader. Later, when I got a press, I got a RCBS primer pocket swage, out of an estate, and never looked back. It worked fine. If I were to to back to using crimped brass, I would probably get another die, or the Dillon unit.

 

[bozo699]

Wayne,
I spend @ least 300 days a year in the loading room and never a single glitch with a primer but I have often thought of what would if one went off? or could it happen? Then I went to work for ammunition plant and learned the processes of ammunition from start to finish,
and I learned that priming mix is way way wayyy more explosive than gun powder itself, I learned you have to work on the equipment with brass tools so as not to create a spark and I learned the dust and residue off the priming mix that settles on everything is kept watered down when it isn't watered down and you happen to step on it, it will pop under your feet as you walk across it or if you drop a tool or something on it POP it goes off. It;s given me a whole new outlook on primers. I have also deprimed 1000s of live cases without a mishap, but I am much more careful now, I clear all powder off the bench, and I drop deprimed live primers into water, if I plan on reusing them I don't let many collect in tray before I empty it. I am very glad you didn't get hurt, thanks for the post Wayne it's a good eye opener for us all, we can never be careful enough.
Wayne.

 

[pyrolater]

I was priming some LC 308 yesterday and was comparing my Lee priming tool to my hardly used RCBS hand aps strip primer. ( CCI primers)

The Lee tool was much faster and lined the case up better. If I had to use a litttle more force to get a primer seated it would go in with out a problem and not leave a mark on the primer.

The RCBS was a pain. the universal shell holder doesn't seem to line the shell up as straight as the Lee and the RCBS would leave a small half circle on the base of the primer if you had to give the primer a little nudge.

Never had one go off though. Is your seating plunger leaving any marks??

 

[15Tango]

Is your seating plunger leaving any marks??

Yes, always has. Never thought much about it. Only does it with SP primers that are thinner than SR primers. I never thought much about it, it doesn't seem to cause an issue. You can actually see that half moon you're talking about in that one picture of the primer in my original post.

Wayne

 

[pyrolater]

I've always used the Lee and the RCBS is new to me. Had to try something different.

I don't know if it makes a difference or not but I don't like the half circle mark.

 

[StevenDzupin]

Dillion tool works well & never had that happen !

Have loaded 1,000's of 5.56 mm US Mil brass

without a problem.

Regards,

Steve

 

[15Tango]

Have loaded 1,000's of 5.56 mm US Mil brass

This wasn't 5.56, it was 9MM. SR primers are thicker than pistol primers so I wouldn't expect it to happen with rifle primers. I've loaded close to 10k .223 with that primer seater and never had an issue with the rifle primers. I'm around the 10k mark on 9MM primers seated with it as well and this was the first time it happened.

Wayne

 

[ChetS]

I recently found a Winchester primer with some priming compound on the outside of the primer. I wonder if the friction of trying to seat it would have made it go off. I just through it away.

Chet