FX Mk2 impact

How low of pressure can I dry fire my impact. I installed the 720 PP and power block and the Oring that is sealing the poppet rod is strangling the rod being new. I've lost 100 fps from my original tune. I greased the rod with silicone grease. I'm figuring if I dry fire it a couple hundred times it will break in sort of like a new engine takes a few thousand miles to break in.
 
Can't answer how low but I would personally not go far below regulated pressure, as you may cause damage with over-travel on the valve. Although you should be able to safely increase hammer strike within factory allotted adjustment.

As to the lower fps, a larger plenum itself will have this effect as your plenum is retaining more pressure during the shot cycle, thus requires a bit more strike to return fps to what a smaller plenum may have given you, as well as your fresh o-ring being a bit tighter.

Its pricey, and won't completely absolve your shot issues but Krytox GPL205 is a great alternative lube to silicon grease that is slicker than snot for such applications with balanced valves.

-Matt
 
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