Are you talking about firing squad victims in general (including civilian capital criminals, and political prisoners) ?
Or just soldiers being executed for cowardice?
Never heard of any kind of firing squad victim going beserk and attacking the firing squad, but I am sure it mustave happened sometime.
Being tied up, and blindfolded, and unarmed, puts you at a distinct disadvantage against seven guys with rifles. Even the guy they give the random blank round to can still beat you with a rifle butt.
But hey...if you're about to be shot- doesnt hurt to TRY to fight back I guess! Lol!