Paul Nassif -- My Gun Protects Me From Crazy Sacramento Kings Fans

Paul Nassif fired back at his estranged wife's claims that carrying a gun puts his children in danger ... stating the weapon is strictly for protection -- from crazy, pissed off Sacramento Kings fans.

Let us explain ... in a declaration filed in the couple's nasty custody battle -- Paul cops to packing heat for the last 9 years (as alleged by Adrienne Maloof in a previous statement) ... but is ADAMANT he has good reason to think his family is at risk and therefore needs a gun.

Paul says that since his sons are the sole heirs to a BILLION-DOLLAR estate they're an easy target. But there's more ...

Paul says he and his estranged wife -- whose family owns the Kings -- have been inundated with threats over the last year ... all because they're contemplating moving the Kings out of Sacramento to Virginia City -- a move that has Kings fans up in arms.

Paul says the tension with the team, combined with their large fortune, puts them in constant life-threatening situations.

Hence the fire power.