Double Firing

[Doug]

My Porter cable RN 175 roof coil nailer double fires when depressed and I pullback on the trigger.

My gun doesn't have an adjustment on the trigger.

What can I service to rectify this.

[UtahAV]

Hi Doug,

I have found that most double firing issues are a result of the gun bouncing when it is fired. You press the gun to the shingle, pull the trigger ans the gun fires. The recoil pushes the gun up just enough to reset the safety. The trigger is still depressed from the first shot as the gun presses against the shingle again and the second nail fires. All of this happens in a fraction of a second. You can test this theory by making a conscious effort to apply downward force to the gun. Use two hands to push down on the gun and see if the problem goes away. If it does it was simply recoil, if not then you will need to dig into the gun. Other causes could be a trigger valve issue, a safety linkage issue or a worn magazine.

I hope this helps,

-UtahAV
-Mark