My 11 year old M2 has not been working properly. It sat in the safe for most of the fall. I tried it on the first snow hunt last week and same ol chit. This gun was just fully disassembled 3 weeks ago by a licensed gunsmith and everything was squeaky clean and in working order. This gunsmith did replace the recoil spring about 3-4 years ago. Is the spring wore out already? Its not like I am shooting cases and cases a year. This gun usually has no problems cycling all types of steel, just a bit picky with trap loads. Its not locking fully on the 2nd shell. If I'm shooting horizontally it will eject and feed new shell completely but not lock/twist. If I'm shooting over head it will barely eject the spent hull. Do I need to run a touch of oil on the rails every couple weeks? Never used to have to use oil all the time with this gun in the past. Is there another part that may wear out over 10+ years of use?