• If you enjoy the forum please consider supporting it by signing up for a NES Membership  The benefits pay for the membership many times over.

Primer Detonation While Reloading

That Guy

That Guy

Banned
Joined
Jul 15, 2012
Messages
1,517
Likes
303
Location
Nobleboro, ME
Feedback: 12 / 0 / 0
Yesterday I had a primer detonate while I was using a Hornady handheld priming tool. This was twice fired brass, Remington primers. No injuries except my nerves - damned near jumped through the ceiling.

Anyway, here's a picture of the bottom of the brass.
IMG_0316.jpg
Hopefully you can see the tiny mark on the primer. Here's story behind that.

I noticed this mark on the primers quite a while ago but I never did anything about it because I assumed Hornady didn't think it was a big deal either. There was a small imperfection on the seat which leaves that mark - I've used it for about 3000 rounds without incident.

After the detonation, I dug out some 1000 grit sandpaper and fixed it. Why didn't I just do this before? Good question. The marks didn't seem anywhere deep enough to cause a detonation and I figured it came from that factory that way, I just assumed it was all good to go.
 
Last edited:
Crap! Thanks for posting..... Glad you were ok..... A good reminder why it is good to wear safety glasses while reloading.....[thinking]
 
That is a surprisingly minor indent to have caused ignition, especially considering all the light primer strikes I had earlier on with high primers.
 
rutilate said:
That is a surprisingly minor indent to have caused ignition, especially considering all the light primer strikes I had earlier on with high primers.
Click to expand...
That's what I thought - I've seen primers with dents way deeper than that and no ignition (especially with 209 primers - I had an O/U shotgun that would really seem to put a deep enough dent, but with any kind of Remington primers just wouldn't set them off). THat's why I was so surprised at this.
 
That does it, I'm doing that to mine as well. I've been tolerating that dimple/indent for a long time now and it only takes one squeeze for me to ruin a pair of my favorite Underoos®.
 
It happens. I had one go off when one of those small primer 45 cases worked it way into my reloading brass containers.
When it worked it way into my Dillon 550, BANG !
 
I've had one ignite and I barely touched the thing. I really suspect I had some sort of static discharge that caused it to blow. Using the Lee Ram Prime apparatus.
 
I too am a little surprised that a dent that small touched it off.

Can I copy that that picture and use it in my classes?
 
BillO said:
It happens. I had one go off when one of those small primer 45 cases worked it way into my reloading brass containers.
When it worked it way into my Dillon 550, BANG !
Click to expand...

Same here I hate the small primers .45 brass
Just one more step for my prep work ;-/


Sent from my iPhone using Tapatalk
 
EddieCoyle said:
I too am a little surprised that a dent that small touched it off.

Can I copy that that picture and use it in my classes?
Click to expand...
Feel free to use the pics however you want. I tried to get another angle of it that might show it better, but all I'm working with is my phone, so not having a of luck.

Is there a chance something beside that dent set it off? That little dent has been on thousands of primers over the last six months, so I'm wondering if it wasn't something else. Maybe a piece of media in the primer pocket? I've jammed these things in sideways and upside down and never had one detonate, so I kind of assumed they really had to be hit just right.

photo (1).jpg

- - - Updated - - -

Royal said:
That does it, I'm doing that to mine as well. I've been tolerating that dimple/indent for a long time now and it only takes one squeeze for me to ruin a pair of my favorite Underoos®.
Click to expand...

It was literally less than a one minute project, BTW. Just laid the 1000 grit paper on the bench, ran the priming ram over it quickly for about 10 seconds and it was done. Which made me feel a little dumb for not doing it before.
 
I doubt it was static electricity. I don't see how it would ignite the priming compound, since the metal exterior acts like a Faraday cage. Have you decapped that round yet to see if there was something lodged in the pocket? Seems like a faulty primer, a small pinprick mark like that shouldn't detonate them. I've mangled them much worse on the 550B, crushed them in sideways and upside down, etc..
 
great, now i need to dig out the rounds where a sliver of brass (from seating a primer in a crimped case) got stuck between the primer and the primer seater on my press dented the primers......

must've been a touchy primer because something that tiny shouldn't have freaked it out.....

thormx538 said:
I've mangled them much worse on the 550B, crushed them in sideways and upside down, etc..
Click to expand...

i LOVE it when they go in sideways......
 
I decapped the shell - as far as I could see, nothing came out of the primer pocket, then again, if it were a small piece of media, it's pretty likely it would have disintegrated/shot out the front when the primer detonated. The primer itself is fairly normal looking, again, deformed by the decapping pin, so not really much to go on there.

photo (1).jpg
 
That Guy said:
Feel free to use the pics however you want. I tried to get another angle of it that might show it better, but all I'm working with is my phone, so not having a of luck.

Is there a chance something beside that dent set it off? That little dent has been on thousands of primers over the last six months, so I'm wondering if it wasn't something else. Maybe a piece of media in the primer pocket? I've jammed these things in sideways and upside down and never had one detonate, so I kind of assumed they really had to be hit just right.

View attachment 109643

- - - Updated - - -



It was literally less than a one minute project, BTW. Just laid the 1000 grit paper on the bench, ran the priming ram over it quickly for about 10 seconds and it was done. Which made me feel a little dumb for not doing it before.
Click to expand...

I had the same issue with the little indent, its on the handheld tool and the single stage press. I've loaded several thousand, but the only time I set off a primer was when I did not entirely remove a primer crimp. You mentioned it was twice fired remington, so it can't be that though. maybe something in the pocket, like others are saying
 
I would call the primer manufacturer about this. They'll probably want the blown one and maybe some samples from the same lot. If nothing else, they'll probably give you something for your troubles like the ammo companies do when you have duds, etc.
 
uploadfromtaptalk1406159191472.jpg
That Guy said:
Feel free to use the pics however you want. I tried to get another angle of it that might show it better, but all I'm working with is my phone, so not having a of luck.

Is there a chance something beside that dent set it off? That little dent has been on thousands of primers over the last six months, so I'm wondering if it wasn't something else. Maybe a piece of media in the primer pocket? I've jammed these things in sideways and upside down and never had one detonate, so I kind of assumed they really had to be hit just right.

View attachment 109643

- - - Updated - - -



It was literally less than a one minute project, BTW. Just laid the 1000 grit paper on the bench, ran the priming ram over it quickly for about 10 seconds and it was done. Which made me feel a little dumb for not doing it before.
Click to expand...

Download a magnifier app. Amazing pics.
 
About 35 years ago I was loading rifle shells with the old Lee Handloader, and using my little plastic mallet to seat the primer, and "Boom" scared the crap out of me but no injury. Use real presses now and no problem ever since.
Glad you had no injury except to pride.
 
EddieCoyle said:
I too am a little surprised that a dent that small touched it off.

Can I copy that that picture and use it in my classes?
Click to expand...

I am more than a little surprised: I don't think the dimple did it. More likely one or more of the three feet on the primer anvil hung up on something (an un-removed primer crimp; some crude in the primer pocket) and crushed the priming compound when the priming stroke was run home.

Primers use chemical compounds that have the property that they form highly attractive crystal lattices and emit heat if the lattice is broken by physical force. The dimple in the photo would not have caused any deformation on the inside of the primer cup, much less enough to cause the primer to ignite.
 
I reload on a Dillon 550 and I have to check frequently to make sure little pieces of debris don't fall down into the primer seating cup or I end up with primers that look like this:
primerdent.jpg

The lighting is exaggerating the dent a little, but not by much. I keep a small airbrush compressor next to my press now so I can periodically blow off any debris from the reloading process. I assume the resize, de-prime, and prime all in station 1 is what causes little shavings to fall into the cup.

I have had quite a few rounds come out looking like the one in the photo, so I guess I am lucky none have detonated. I only use CCI small pistol primers. I clean my press at the end of every reloading session.
 
Couple of things to ponder while you guys are using the hand primers to load the primers into pockets:

1) Primers go bang when you depress the cup enough to come in contact with the anvil, at a certain speed......

2) That is to say that if you do it MATRIX slow, it won't likly do the same thing as it would when you are going faster.

3) Hand priming tends to go faster than on the press priming, simply because when assembling ammo on a progressive, there's a lot of other things to be watching for. Therein lies the danger.... Slow down when hand priming.

I've installed plenty of primers upside down, sideways, and even with powder deposits on the primer installer pocket on my RL550b. I've never had one of them go bang or boom in all these years of assembling ammo. It's because I am not in a race to assemble the most number of rounds per hour. Or, install primers as fast as I can, to get them done while the TV show is on.

Slow down. Watch what you are doing. Assemble good quality ammo, not fast ammo. Wear eye protection. Remember that those primers that you love doing now with the hand primer tool, will come back to curse you when you are 60+, and your hands are old. I've never installed a primer with a hand tool.

Anyways, that's my two cents worth.

Greetings from Florida!
 
Had my first primer detonation today after loading more than 80k rounds. My new xl650 Dillon, started having issues with primer seating on 9mm after doing a conversion from .38 to 9mm for the first time. I had one or two primers fail to seat (military crimped pocket) which left some loose powder and I believe this started to gum up the works. Eventually this lead to about 4 crushed primers (I had slowed down quite a bit at that point to monitor things more closely) then a BANG!
With my LEE system I never had an issue quite like this but then again I never achieved speeds like this before. I guess with the new caliber setup I need to take it slowly until things are running smooth. This includes better case examination prior to loading (especially the primer pockets) and a can of compressed air to keep the case shell area clean.
 
Just so you know, I had occasion to open a box of Fiocchi something or other and at least 50% of the primers were creased to some degree.
 

Similar threads

reloading 8.15x46r
Replies
20
Views
233
Stee
S
show us your reloading room
Replies
3
Views
94
peterk123
P
Shotgun reloading classes
Replies
7
Views
208
EddieCoyle
EddieCoyle
12ga Reloading for hunting.
Replies
9
Views
258
DW357
DW357
Bullets to keep cost down on reloading 223?
Replies
18
Views
497
EddieCoyle
EddieCoyle
Back
Top Bottom