jerc This is what it's all about, so you can verify how accurate a player is potentially. I mean how many shots the player has taken to kill a certain number of enemies, i.e. if a player has taken 100 shots of primary fire in a game and killed 100 enemies, his accuracy is 100% (this doesn't happen unless you are dealing with a cheater or bot set to godlike), if he killed 50 enemies while firing 100 shots, his accuracy is 50%. This accuracy of primary fire cannot be higher than 100% because you can only kill one enemy with one shot.
As for shock balls, I have basically doubts.
Let's assume that the player is constantly smashing balls (e.g. Mr. Caligula) and during the entire game he kills 200 enemies while firing 100 shots at shock balls, his accuracy suddenly increases to 200%. And here comes the problem, there is too big a gap between these types of fire. Then you won't check how well the player mentioned at the beginning shoots, because it may turn out that it's just Mr. Caligula π