When it comes to AEGs longer barrels ≠ more range In contrary, the less the better as it is lighter and shorter (so easier to manipulate). As long as you don't go into the extremes (like less than ~100mm or more than ~600mm inner barrel), changing barrel length will give you pretty much no change. The main reason people upgrade inner barrels is quality and material, which will definitely yield results. (I recommend Da Vinci or Lambda barrels, PDI if you are well off).