A tight bore barrel noticeably increases the accuracy of your AEG over the stock barrel so you will get tighter shot groups. Since the barrel fits tighter around the BB your compression will also increase which can boost the guns velocity by 10-20 fps.
Please note: The additional notches CNC milled into the sides of this custom barrel is for locking the AAP-01 upgrade hop unit securely to further reduce movement and vibration in use.