John F

If you have fired it that many times and still have the copper colored anti sieze gunk you are not cleaning it well enough. That should all be gone within the first couple hundred rounds as it is meant to keep the gun from siezing not a lubricant. With all that residue in the gun you are filling spots and lowering the tolerences. It could have been you that caused the double tap but the fact that it was so easy to do is more likely to have occured because of a dirty gun.

A big part of it is fairly dependant on your discipline. If your shooting competition then you should focus on the distance requirements of that. For example PPC outdoor shooters should focus on from 25 to 50 yards. If you are into steel challenge then a majority of your focus should be 30 to 50 feet. If you are into defensive pistol shooting then your main area of practice should be at 50 feet and less with a majority of the focus less than 30 feet.