This mod gives you better weapons stats and better ranges.
It also let's you use the 9mm pistol like a cop.
How to install?
Paste the weapon.dat file into
... \Rockstar Games\GTA San Andreas\data
Best to be used with Glock 17 mod
http://www.gtagarage.com/mods/show.php?id=27150
This mod will make some missions extremely hard.
Backup weapon.dat : http://www.gtagarage.com/mods/show.php?id=27152