Well, the difference would be that a 15-bullet burst could act as a variable damage since you can evade some of them... but one bullet * 15 damage can not, it's either you get hit (and most likely die from the multiplier) or not.
I think a way to do a burst would be to alter the shooting delay of the weapon, making it shoot verry fast... and count how many times he fired and block him from shooting a short period of time at your desired number of shots.
That won't actually act as a burst since you must hold down fire to complete the burst but it's more than nothing
And yeah, don't ask HOW, search... there are plugins that alter gun shooting speed, the rest you figure it out
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