Excellent topic with excellent info, keep it up guys!
Edit: Actually, Sha Do said something that I think is VERY important, distance training. I know he teaches that with his course, but not every one can attend (some don't need to), but I feel it's one of the biggest responsibilities than anyone with a sniper rifle should learn. I trained myself, it's easy, challenging, and addictive. Every day life, when on the street, sitting on your front or back porch, look at objects and guesstimate the range. I do it all the time, have since even before I got my first sniper rifle. Started with my measuring with boots (12" soles exactly) out to trees in my back field from my porch, hung a bright orange ribbon on a tree 100ft away, one on a tree 150ft away, and there's another tree out back that stands out, measured 230ft away. When ever you get the chance, look at those objects between you and it, and study the distance (amount) of ground in between. Using the height of objects, such as 6ft tall guy, isn't always the best, because not everyone stands that height or even tall. My method works for trees, walls, prone guys, etc. and am generally within 20ft of being correct. Am always on with the 100ft engagement distance I religiously stick by (been times I've not pulled the trigger even though the guy is 100-110ft away, due to not feeling comfortable with it because little branches or something in the way and don't want to risk having my BBs tick one and hit the guy in the mouth or something.) So, try those simple exercises out when you can and always, it's a decent way to pass the time wherever you are (except in small rooms of course!)