The link is provided below, along with the two most salient paragraphs. But I want to add a couple of paragraphs describing my own experiences:
(1) Several years ago, I and my Significant Other ("She Who Must Be Obeyed", or SWMBO) were competing in a USPSA/IPSC match at *Un-named Gun Club*, when during a reload with her STI Race Gun her firearm discharged. She had held her pistol tilted dramatically high, and I KNOW it was a "Slam Fire" because I was the Range Officer and I was watching her carefully. I Disqualified ("DQ") her, not because I thought she had her finger on the trigger during a reload (which is a DQ-able offence in IPSC/USPSA ... and she did NOT!) but because her muzzle was pointed high and I was sure that the round had left the range. Read: Went Over The Berm
(2) Moving forward a decade or two, I now teach a class in "Introduction to USPSA" for new competitors, and I tell this story to every class. However, I don't make an effort to emphasize the lesson learned ... always keep the muzzle below the berm.
(3) Significantly, the same range where SWMBO had her Slam Fire episode has in the past few years added a new Range Rule: "Thou Shalt Endeavour to Keep Thy Muzzle Below The Berm, else suffer the Consequences of the Match DQ" (or words to that effect). Call this "Rule #3".
Local competitors who attended USPSA matches at *Un-named Gun Club* have addressed this to USPSA, which organization has 'disenfranchised" the club from holding "USPSA MATCHES" because the club enforces a rule which is not supported by USPSA. Or IPSC.
[So *Un-named Gun Club* continues to conduct "USPSA-TYPE" matches, but they call it something else. I'm told that they *generally* follow the conventions of USPSA competition (many of which are shared by Defensive Concealed Carry Competition), plus their own local rule, but they don't send the results in to USPSA and competitors are not compelled to shoot a "classifier" stage. Since USPSA doesn't acknowledge the club rules, and USPSA intellectual property (classifier stages, the rule book, and the name of the organization) are not involved, competitors are not credited with competing in an "organized" match.
Essentially, it's just a Fun Match.
It's also an opportunity to spend a pleasant day at the range with your friends, and to get some good solid gun-handling practice under your belt.]
Now, I had thought that Rule #3 was a bit of overkill (forgive the expression), but I had never actually thought it through ... despite my own personal experience. However, considering the lesson provided by Kathy Jackson (link, and some text, below) I think it's something that I ought to emphasize in future Introduction to USPSA classes.
NOW read Kathy Jackson's comments, or preferably follow the link to the full story (Read The Whole Thing).
Keep the Muzzle Below the Berm | Cornered Cat:
There are far more instances where a gun fires upon slide forward (eg, “slam fire”) than I thought, and many instances where people in a hurry or new to the gun suffer a sympathetic squeeze reaction and fire the gun when they intend to either drop a slide or release a magazine. In most of these cases, the only thing that prevented serious injury or death was that the user fortuitously (sometimes deliberately, but more often fortuitously) pointed the gun in a safe direction. \
Why are so many instructors and accomplished shooters encouraging people not to keep the gun pointed in the safest possible direction — at the berm — during the reload? What benefit could possibly outweigh the risk of deliberately, repeatedly, and habitually violating one of the fundamental safeguards against death or injury while handling live firearms?*(Again, go RTWT)