Buck Turgidson wrote:

I probably watch too much TV, but there was a CNN report this weekend about
a guy having a framing nailer backfire, and a nail end up in his mouth
(unbeknownst to him, but that's another story).

I can't find much on this on the Internet, but am wondering how common it
is. Doesn't sound like a lot of fun if it happens. I guess when using my
Senco finish nailer, I'll make sure I am not directly behind it.

I'm sure it was not a "backfire" in the sense you're implying you're
thinking...

There was another thread where I posted my conjectures based on what I
saw/heard.

As for frequency, it happens (by "it" I mean folks getting shot, not a
gun ejecting a fastener directly rearward, that's not possible by any
mechanism I'm aware of). In fact, the hospital noted this was the
second such case they had had although it wasn't stated as to how long
ago.

A lot of incidents are richocets or the "I was reaching around behind to
get to XXXX and it slipped/came through the side/other silly thing"
type...

I have had the trip safety mechanism fail on the rare occasion.