This glitch only works with the famous, first of all get yourself a famous and shoot it a few time notice how it shoots three bullets at once wel to do this trick right you need to shoot the gun and before it finishes firing the three bullets you need to swap to a different gun not the katana or it won't work this may take a few tries but it does work. Don't upgrade the gun before doing this glitch.
Attack with katana do Chainsaw Damage
his glitch is quite easy all it requires is a chainsaw cost 200 in game money and a katana press 3 on the keybord so how this trick works is simple start attacking with your katana and switch to your chainsaw easy notice how when you stop attacking you are holding the chainsaw not to worry thats part of the glitch just attack again and it will go back to a your katana but still doing chainsaw damage.