Create a cfg file named "shot_select.cfg" without the " " . Copy Paste this code into there. When you join a server, open the client console and type "exec shot_select" without the " ".   

The "q" button will cycle between Full-Auto (medium crosshair size) and Single-Fire rate (tiny crosshair size). So the crosshair is a visual indicator of which mode you are currently using and the tiny crosshair single-fired is awesome for long range accurate shots!!!!!!!!!!!!!!!!!!!!!!!!!   

If you want to change the button used to cycle modes change everywhere you see a "q" in the code to something else you want instead. You can also customize the crosshair sizes you want during each firerate mode by changing the number after each "crosshair_scale". The larger that number the smaller the crosshair size.   

Practically every gun in CS:S has the choice between semi-auto/Full-Auto in real life, but not Burst. So this script keeps the realism high.   

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alias "wait5" "wait; wait; wait; wait; wait";   

alias "burst" "+attack; wait5; -attack";   
alias "+normal" "+attack";   
alias "-normal" "-attack";   

alias "burst_bind" "cl_crosshairscale 4000; bind mouse1 burst; bind q normal_bind"   
alias "normal_bind" "cl_crosshairscale 900; bind mouse1 +normal; bind q burst_bind"   

bind "q" "burst_bind"   

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