First, are you using light 2 3/4" loads? Have you tried cycling the 3 shells by hand? Because if your using heavy loads and the shells will cycle by hand, it is most likely in your recoil spring tube.The more gummed up your tube is, or dry, or cold, the heavier the shell it will take to make it cycle. I would take the bolt out of it and take your butt pad off,depress the recoil spring plunger with a pencil, and shoot some good cleaner down the tube a dozen times working the pencil in and out ( working the spring good).A 20 gauge felt swab on a clening rod will work good. There is a hole at the back end of the recoil tube that the dirt and cleaner will run out, so keep your gun straight up and down with the barrel end in the air and the butt on the floor. When the cleaner starts coming out of the stock clean (clear)looking, then oil lightly (the inside of the tube) good with clp breakfree. That ought to make your gun open and slam shut just like a new one. With only a 1000 rounds through it , it's not even broke in good, It's probably not a broken recoil spring unless you got a defective spring ( freak deal). Keep us updated.