I also have a chrono and a seriously modded blaster using a singled berserker tank and can confirm if you're using the right darts for your barrel you're probably hitting around 250. I was able to tune mine down to 180-200.
I am comfortable playing higher fps caps but a hard cap of 200 lets people compete more casually and draws bigger crowds, as mentioned. If it's just you and your friend, go nuts (but I recommend full face masks because split lips suck). You might also want cups.
How were you able to dial it down? Just fewer pumps or what?