To answer one question:
First, as most here probably know, it IS possible to survive a head shot. It is even possible to fight with purpose, after a head shot.
Thus, your placement MUST be precise.
The shot that must be executed is one that turns off the lights NOW. The target simply freezes, then falls like a tree. No twitches of the finger, no final breath, no movement, NOTHING. There is one--and ONLY one--shot that will ensure this, and that is the "pons" shot.
This shot impacts and destroys the brain stem--the nerve and communication center of the body. ALL functions of the body go through this nexus. Once destroyed, the body simply ceases to function.
The aiming point for this shot is determined in this manner:
For a target (head) facing you, visualize a T. The arms of the T take in the area of both eyes, to the edges of the eyes. The bottom of the T goes down to the bottom of the nose. The optimum aiming point for this shot is the bridge of the nose.
For a side shot, the area is much smaller. Aiming point is the auditory canal of the ear.
From the back, the area of the head where the curvature of the skull starts sloping downward toward the neck is the desired target.
Making a shot like this--under these circumstances--is part training--but the majority is MINDSET.
You must mentally prepare to make the shot. Once you have committed, the trigger MUST be rolled smoothly to the rear. Firm grip, sight alignment, sight picture and trigger control is paramount.
Another element of making a precision shot is follow through. You pull the trigger without disturbing the sights. When the weapon fires, you continue pulling the trigger to its fully rearward position, while you reacquire the target. The trigger is then released to the reset position in preparation for another shot.
The point here is this, people--when the time comes, the time for rationalization is OVER. Your family member is in the grasp of an ANIMAL. You have the responsibility to protect your family.
There can be no rationalization, and there is no room for fair play. There is only room for ACTION. Do not hesitate, and do not second guess yourself. This is where training and the acquisition of proper mindset comes into play; you must be mentally equipped to take the shot when the time comes.
I know what some of the posters are saying, and I have read the "ninja" posts. All I will say is this:
I have trained for most of my adult life to take this shot.
Part of that training is competing in Conventional Pistol (NRA). I can place an aimed shot, with my 1911 or Glock handgun (or any handgun in my safe) into a 1" circle at 10 yards (the longest distance in my house right now) 100% of the time--without fail.
A second part of my training is from law enforcement qualifications. Our qualifications begin with a stage that requires you to place 2 rounds COM, then two rounds in the head area of a B27, within 3 seconds. This is from a fully secured Level 3 holster, and you start in the "interview" position. My first two rounds are X ring shots, and my second two are less than 2 inches apart, centered on the head.
The third part of the mindset comes from 15 years as a soldier, training to actively engage the enemy at all ranges from hands-on to long distances.
My wife is my world. We have been married for almost 28 years; she is my best friend and my companion.
Any person who lays hands on her with hostile intent will be dealt with--swiftly, without hesitation, and without mercy.
And that's all I'll say about that.