It doesn't reallt matter..........I guess any smaller paint works best
Its a nice basic design
Throes made curve balls
Let me first say im not totaly prejudice to this barrel, I just don't like it. I don't know if maybe i juts couldn't match the paint that well but i think this barrel isn't as good of quality as a stock spyder. It kept throwing curve balls and almost never put a paintball next or near to my last shot. I was very disapointed because i had chosen it over the excel. I'm not and excel fan but the quality is better.
Maybe i just got unlucky but I wouldn't recomend this barrel to anyone. Get a excel or even a teardrop.