When paintball guns are designed and built, the company making them can’t know what brand of paintballs you’ll shoot or what conditions you’ll play in, so the barrel that comes with your new paintball gun will be a basic one, able to shoot almost any paintball reasonably well. One of the best paintball gun upgrades a player can invest in is an aftermarket paintball gun barrel, because this instantly improves accuracy and overall performance of practically any paintball gun! A good upgrade paintball gun is designed to improve accuracy of a paintball gun by adding length for tighter groups at longer range, some porting (drilled holes) to ease the turbulence of the paintball as it transitions from barrel to open air during flight and to reduce noise, and will generally feature a better honed or polished internal finish that will reduce friction and drag as each paintball passes through it.