this thread is slightly relative to talk about "g_realism 1" because this is discusion how blood splater effect should work/should be replaced.
What i was thinking as realistic way is that you say how you would act when getting shot.
Ofcourse when you get shot to hands you might curse something and/or whisper something (uggh, ouch or other stuff like that) some might scream. And accuracy may throw a lot.
Legs may cause more pain and make you fall down. Or just slow you. Still throws accuracy.
Stomack shot is incredibly painfull and you some can even take 8 shots before dying.
Headshot pretty much kills. Also chestshot is dangerous.
But how these should be indicated? Think how you would act after getting shot. I think blood effect is useless because headshot usualy WILL kill you. Also you shouldnt see blood spraying if you get shot because your suite sucks pretty much the blood.
Thats sure that highest effect you should get from stomack shot. Also the shot to the ballz will hurt like hell i think
and is fatal. Because much big blond vessels are located on that area...... seriously 
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Also thinking that nades will cause small force waves which will effect trough some objects. Makes you dizzy.
Also what i think is that when getting bad shot you might hear your heart pumping or that anoying high voice on your ears (not remembering the word lol)
Also knock effect would be pretty optimal.
This is messy and not telling how we should excatly do splater but now YOU tell what to do for it be more realistic. Everyone might react differently.
If this wont get to vanilla CQB we still can suggest it for g_realism cvar.
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