This has been going on for well over a month . The gun has had about 300-400 rds put through . The gas ports are clear , the gun has been cleaned thoroughly , the gas piston hardware has been checked against the manual over and over . There is no evidence of gas leaking out the top of the O ring . The chamber felt like it could have used a little smoothing up . The loads that I am having trouble with is a win AA hull 14.7 grs of green dot , win waa20 wad win 209 primer and 7/8 oz of shot . The load is supposed to generate over 10,000 psi of pressure and that should be plenty to cycle a gas gun . I shoot one of the lightest loads I could find through my 391 Optima and never have cycling issues . The Rem will cycle the bolt far enough to lock it open , but , it will not eject the shell . The rem is chambered for 3" mags and the hulls I am reloading are 2 3/4" and have only been fired once maybe twice so I couldnt have imagine that they have stretched any let alone stretched farther than a spent 3" . There isnt anything wrong with the extractor it grabs the shells and sometimes even stove pipes them , but , very rarely throws them out of the receiver so another one can take its place .