Well this is my first post did some searching and couldn't find this so figured I would post it(since I love this site and don't want to lose my login). Easiest way to lvl your ranged weapons is to go to Dr. Boom in Netherstorm and target his bombs. It may be a little boring but seems to work nicely. If you don't know where im talking about here is a picture.
Hope this helps somebody and if its already been posted please delete. This might be more of an exploit than a guide but wasn't sure where to post it.