I had a wake up call a couple days ago. I was watching TV and priming some freshly trimmed 223 cases with my Hornady hand primer.
I am no expert reloader, but I'm not a novice either. I have reloaded more than 15000 rounds in the past two years alone.
I was grabbing brass with one hand, and priming with the other. One piece of brass seemed to resist the primer a bit, so I squeezed a little harder and BOOM! The primer detonated!!
I always make sure the case mouth is pointed away from me, but when it did not seat as expected, I must have tilted the case toward my face a bit. I saw a bright flash and char-broiled my finger.
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It was like setting off a firecracker in your hand. I was immediately thankful that I had my glasses on when this happened.
This is only the second ND of a primer I have had. The first one was undoubtedly my fault. I set that one off with a deprimer die, when I first started reloading.
So what happened? Did I forget to swage the primer pocker? Did the primer go in sideways?
Upon further inspection, I noticed that the primer was still flat on the outside and did not have dimple from the hand primer.
I think it was a defective primer. Maybe the brass was soft. Maybe it was not the correct diameter. I may never know.
Bottom Line= WEAR YOUR SAFETY GLASSES AT ALL TIMES WHEN RELOADING!