Exploded head is back upon reload

[SAC]

 

I am using target.Dismember("head1", true, false, false) is a script to blow npc's heads off, and it works brilliantly.

 

However, the problem is their heads are back when I reload (minus a red gash across the throat) and I am not sure why. I'm not even sure if it's a mod I'm using, or a game engine quirk.

 

Any ideas?