hpr should be at 200 psi and your dwell at 10 blinks (stock) back the lpr screw all the way out then keep turning it in until the marker fully cycles.then finally give the lpr 1/4 of a turn inwards..this should set your velocity at around 270-280 depending on your ball to barrel match. if the hpr is set to 280psi+ the solenoid will usually self vent thus preventing any damagehpr should be at 300
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http://members.iinet.net.au/~chdw/borgfocus/troubleshooting.html