Do longer airsoft gun barrels give better accuracy?

Hound is right, there is a point where a barrel is just to long and it can negatively effect your accuracy and range. but with those guns you are no where near that point. go with the longer barrel, it will be more accurate than the shorter one.

Sorry, but the long barrel myth is just that; a myth. Past a certain barrel length, it all depends on your hop-up system and FPS (a result of how good your compression is, the quality of the barrel, etc). The reason a longer barrel makes a real gun more accurate is that there is room for more rifling and more gas expansion.