Yesterday I noticed that the deactivation lever on my Excalibur 315 was not always returning to the rear. When I pushed it in to uncock the bow the lever stayed forward and the dry fire arm stayed up. Thus the dry fire system was deactivated. If I pulled the lever back the dry fire arm dropped down to its correct position. I removed the 4 screws that held the Dryfire bracket on removing it from the trigger housing. Attached to the lever is a long "leaf" spring. The spring was sliding under the block that holds the dry fire arm. It was an easy fix. I removed the screw holding the deactivation lever to which the spring is attached. Cleaned the lubed the lever and reassembled it insuring that the end of the spring was position on the back of the block NOT GOING UNDER IT. Works like new. If you push the deactivation lever in slowly and if does not fly back with authority your spring may have slide under the dry fire arm block. I used blue locktite on the screws that hold the bracket to the trigger. You do not have to take the trigger out. Also it is a good time to check on screws with a torque screw driver.