system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] Tons of questions about aiming spells.

0. Do you always have to wave your wand in order to cast a spell?
0. If so, how are you supposed to aim your spell while your wand is moving around?
0. Why aren't wands made to be more like guns? With sights on the top and a handle that's nearly perpendicular to the "business end". As a wand is right now it's impossible to look down the barrel to see where you're aiming since you'd need to turn your wrist in a very awkward angle.
0. Under ideal circumstances, how accurate are spells? Do they shoot perfectly straight forever?
0. How small of a target can the average wizard hit accurately?
0. Are there wizarding snipers? Or wizards who are trained to shoot spells from long distances with extreme accuracy?
gpt
1. No wandless magic is a thing.  It just helps.  
2. Depends on the spell.  Usually the last bit of movement as the spell is coming out.  Many just require you to think of the target.
3. The wand is a conduit, and it being the shape that it is is conducive to that purpose.  Aiming is also partially mental so a gun shape and sight wouldn't help much.  
4. Again depends on the spell.  Avada Kedevra keeps going forever until it hits something, most spells will dissipate after some distance.  
5. Human sized.  Since most spells don't matter where precisely they hit on the body, most wizards don't bother trying to get more accurate.  Spells meant for particular purposes have some manner of seeking to them.  
6. The ministry has not cleared you for this knowledge.