On an autococker, or any form of poppet based gun, there is a sweetspot to the reg. If it was on a graph, pressure on the x-coordinate, and velocity on the y-coordinate, it would look like an inverted V. Basically, if you raise the pressure too high, the hammer won't be able to open the valve, because of the amount of pressure. So, the higher you raise the pressure, the lower the velocity will go. You want the reg somewhere around 350 PSI for a full sized cocker... I'm guessing around 450 for a mini? So basically, you'll have to continuously lower the reg until it starts to shoot right(keep in mind it takes a few shots to make the reg actually change. The reg can't change the pressure of what's already in the dump chamber.)
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