Soundguy, we each have our experiences and draw our own conclusions from them.
For me, I NEVER pick up a gun and/or pull the trigger except I want something DEAD (practice and transportation needs excluded). If I don't think it's a dead shot, I don't pull the trigger. I select the ammunition and shot placement to do the job in one shot. I'm not always a perfect shot, but recently shot two Axis deer. One in the head (immediate drop) and the other exactly in the chest cavity as it moved thru a 2 ft diameter space in very thick brush (ran 30 yards). One 30-30 shell each. I either eat it, or am protected by the shot. I recently shot a rattle snake, dead, .22 at night in 3 foot high weeds near my house/workshop.
For me, pulling the trigger inside the house means only one thing... all other options are exhausted and the threat is an immediate deadly risk to my person or family, and must be terminated immediately, not just slowed down.
If I were a laywer (I'm not) defending a client who had violated all the lights, alarms, locks, dogs, verbal commands to leave, etc. and recieved one load of bird shot, then a subsequent heavier load, I would argue that "unnecessary force" was used since the first shot would have clearly incapicated the perp and anything else is just too much. The actual facts would not matter to me, as a defense laywer.... and there is always the possibility of the perp sitting there forlornly looking pathetic with whatever injuries sustained being exaggerated and protesting that it is all a misunderstanding and he's not to blame and is now harmed for life and needs compensation. This argument would be particularly compelling if you managed to get the shot off before any actual physical harm was inflected on you or any family member.
One must think carefully about how aggressively you intend to defend your person and family under extreme and immediate risk situations.... do you intend to wound/slow down the attacker, or to kill? It's not only a moral issue, but there are legal rammifications and probable consequences/outcomes to consider in each case.
Everybody contemplates their belly button and comes to a conclusion of action, inaction and preparation that meets their situation.
Skent, congratulations on all wife and daughters knowing about shotguns... I used a .410 single shot until I was out of college. Often I put more birds in the bag than buddies with automatic 12 ga. shotguns. Certainly, my ammo cost was less.
