What's everyones opnion on barrel length? I've had good results with barrel extensions on cqb weapons like mp5's and m733's, giving them better groups at 100ft out, but what about on the really long rifles? Do you still see any improvement with anything more than 4 or 500mm of barrel? When I switched to a tbb on my s-system, I almost got the 509mm with a mock supressor, but I thought it would be to cumbersome in the dense brush we have in this part of the country, so I opted for the 390mm instead. Maneuverability better suits my playing style, but at a D9 game Cody had a rifle that could out-range just about everyone. The thing was as long as a boat oar, but he easily held the line at 200ft away. I've also heard that at some point you begin to actually lose energy with too much barrel length. What do you guys think?