Reasonably intense range session today to see if my barrel throating work held up on the 9mm Springfield Range Officer Compact. 260 combined rds of Fiocchi 115gr, Speer 124gr and S&B 124gr ball ammo followed by 40 rds of various JHPs made by Sig, Federal and Hornady. 0 failures to feed, eject or go into battery. 0 jammed rounds. I did have some failures to lock back on empty with two aftermarket mags. The failures were repeatable and these mags were unreliable with all three ball ammo variants. The followers in these mags may have been damaged in some of the severe jams this gun had previously or they may just not be reliable in this gun. The Springfield OEM mags ran 100%. For the first time since I bought this gun on July 5 2017 it ran reliably. I have never put 300 rds thru it without a round getting stuck in the chamber. I'm not sure but I don't think I ever put more than 50-75 thru it without a problem. It's been to two gunsmiths and neither fixed it. It took me about one (supervised) hour in my gunsmithing class using some needle files, Cratex nubs and felt bobs with a little Flitz polish to get to the heart of the problem and make this gun reliable. I could have returned it to SA for warranty repair but I knew I would eventually learn enough to fix it myself. It took me a while. It's been 15 months since I shot it - when it failed it's first range test after being "repaired" by the second gunsmith - but today I feel good about it finally being reliable. Now I can move forward and do a few things to make it smoother, nicer and more enjoyable to shoot.