My advice, learn the 5 rules of a gun fight and then learn what they really mean and how to apply them.
1) gun beats no gun
2) a hit beats a miss
3) fast beats slow
4) big holes be little holes
5) two holes beat one hole
Wise advice - and a lot of similarities to the four "Rules of Carry":
1) Any gun is better than no gun.
2) A gun that is reliable is better than a gun that is not.
3) A hole in the right place is better than a hole in the wrong place.
4) A bigger hole is a better hole.
;^)