Metalkill
Yeah this is totally possible. Pay close attention at 1:20 in my video link below
http://www.youtube.com/watch?v=alKe3ZZoTLs
I expanded upon this idea to have an explosion decal which ran once then disappeared followed by a raging fire decal which continued looping afterwards. You could just go ahead and leave it at the explosion decal which will suit your requirements.
This requires 2 scripts which I'll upload with instructions after this post.
-Edit (the scripts are now attached to this post).
If you imagine the idea in your head. You can make it happen in FPSC!