I have a Benelli Nova that does the same thing. I detail-stripped and cleaned the action and it continues to misfire. There are all kinds of recommendations out there from "a good cleaning" to "cut two coils from the spring." Lots of posts out there on other forums. The only Benelli shotgun that doesn't seem to have problems like this is the SBE. This is one firearm I've been sorely disappointed in and won't buy another.