Two questions about killing curses

[snorkackcatcher]

(1) Is it reasonable to suppose that an Avada Kedavra cast with insufficient power or determination to kill would nevertheless still have some effect (act as a powerful Stunner, leave a scar, whatever)? Points I can see in favour of this are Fake!Moody's comment that he probably wouldn't even get a nosebleed if the class tried the curse on him, and

Comments

[masterofmystery]

1. Maybe with Harry's case of surviving it, it was a Curse used to its greatest potential in that it was meant to kill and would have had it not been for all the reasons it didn't. I guess we'd need other cases of when the Killing Curse wasn't used proficiently, but I think it's safe to say that, what, if it's done without the greatest amount of power (like Harry's crap attempts at the Cruciatus), then maybe it's not as bad? Still, you're supposed to got Azkaban if caught casting the spell, but does it say whether or not they go if it's done to the most power? If Harry didn't have all his protection and was busted for doing those rubbish attempts at the Cruciatus, could he have gone to prison (even though he's a kid)?

2. I've seen theories that it could have been, but what about the colour of the spell? It was purple when it hit Hermione, right, but there was no colour when Harry hit Draco with it, so that's why I've been a bit wary of it. I know Dolohov couldn't voice it, but because of that it's suddenly a bright colour and flame when he did it and when Harry does it there's nothing? Something about that just doesn't sound right about it, so that's why I've always thought that maybe it's just another Dark spell.

[snorkackcatcher]

1. That would be the way around it -- but the problem is that it would be hard to tell if someone survived because the curse didn't have enough power. I could probably say something like it can release a blast of magic even if it doesn't work.

2. The colour of the spell concerns me too, but the problem is that JKR does seem to change descriptions of spells from book to book. For example, Expelliarmus when we first see Snape use it In CoS it produces a flash of light, but otherwise doesn't seem to -- it seems suspicious that we have two very similar looking spells and that the first time it's shown, the incantation is carefully not mentioned?