Recently acquired a "A" grade fox 12 gauge serial number 20830. Really like the gun but during dove hunt discharged the left barrel first and both barrels fired. At that point I loaded just the left barrel and fired the gun and the right hammer dropped every time. Fired the right barrel first numerous times and every thing OK. Gave the gun a cleaning and appeared to have solved the problem. Later replaced the axle pin for sears that I damaged during the first cleaning and gun back to doubling when rear trigger is pulled first. The reason I replaced the sear pin was during the cleaning approx. 1/16" of the sear pin broke. Still functioning but not happy with damaged sear pin.
I have fired the right barrel first several hundred times with no doubling. I guess my question is; can tightening the tang screws affect sear engagement? Between cleaning and sear pin replacement I fired the left barrel first 3-4 times and everything OK and I hoped the problem solved, but after installing new pin problem is back. I suspect I need a good trigger smith unless someone can offer something else I can try. Thanks