I purchased a 1943 long Branch Enfield No 4, Mk1 @ the Mesquite, TX Gun Show earlier today. Arriving home, I gave it a thorough cleaning. After reassembly, I closed the bolt, applied the safety then pulled the trigger. I heard and felt 'something' inside the action 'click'. Releasing the safety, the striker dropped to half-cock but would not fire when I pulled the trigger. Concerned, I repeated the process w/the same results. This happened every time I tried. If I close the bolt but do not activate the safety, everything functioned properly when the trigger was pulled. Did I reassemble the trigger/trigger group incorrectly or is there another cause of this malfunction? I also have a No4, Mk 2 but I believe the trigger guard/group may be different. I have not fired it but 9-10 shots and that was several months ago and I have it put away so it is not readily available for comparison. Any suggestions would be graciously appreciated.