There is a mod they had for PC halo ce and it eliminated the pistol lag by speeding up the pistol bullet itself. Why not make it max speed? It’s the backbone of the game and, if you have the Jedi like skill, three shoting with that most holy of pistols is all you really want in life.
SPEED UP THE PISTOL TO ELIMINATE BULLET LAG!!!
Read more about it on halobugs.com