Underbore / Overbore question

[frenchy2475]

Or poor paint no matter what barrel your using, you won't hit ****!

I use a .689 for everything

 

[WildWayz]

Also, some markers like the Axe with aftermarket bolts, you HAVE to underbore it otherwise it won't hit the required velocities and keep the low pressure.
But some markers like the Alien Invasion you have to overbore it one size.

If you overbore it one size, it means that it deffo won't break paint if the ball is a bit bigger than expected. Also even if you use the same brand of paint, they may be from different batches so may be slightly bigger...