Maybe try googling auto hotkey.. Idk tho!
Put this in a text document(Notepad works...
Ins::Suspend
LButton::
Loop
{
SetMouseDelay 8
Click
If (GetKeyState("LButton","P")=0)
Break
}
Save it as anything but at the end you MUST put .ahk
Save it to your desktop, then double click or right click and hit run script. And there you go, but it's better to still tap the FAL, since its recoil is pretty bad.