Opinions and other ideas are welcome.
Deadly Misfire with a Firearm: Each time the damage from a firearm misfire takes the gunslinger to negative hit points, she regains 1 grit point. Such a deadly misfire must happen in the heat of combat. A deadly misfire that resulted from an attack on an unattended object, a helpless or unaware creature, or a creature that has fewer Hit Dice than half the gunslinger’s character level does not regain grit.
Mass Scatter Shot with a Firearm: The first time a gunslinger successfully hits 3 or more enemy creatures with a single Scatter shot attack during the course of a day she, regains 1 grit point. Such a mass scatter shot must happen in the heat of combat. A mass scatter shot that deals damage to an ally, a helpless or unaware creature, or a creature that has fewer Hit Dice than half the gunslinger’s character level does not regain grit.
Um... you do realize the only way for a gun to misfire in such a way as to harm the gunslinger is for him to let it blow up right?
Meaning he's out of a gun and the HP (and the damage isn't going to be enough to drop him either).
Which is especially silly when you consider he has the means to prevent this from happening.