Just bought the GSG 522 on tuesday and had my 1st chance to shoot it today. Had a great time. I did the hammer strut mod befor i ever put any rounds through it and it performed flawless. I tried 4 differents types of ammo: Federal Auto match, CCI MiniMag HP, CCI Stinger, and CCI AR Tactical. All were good but the CCI AR Tactical had the best groupings out of the bunch.
Just bought a box of the CCI AR tactical. So far this is the best ammo for my M&P 15-22. I have had nothin but trouble with the federal 550. Empty cases not ejecting completely from the ejection port. The CCI Tactical groupings were nice and tight, about 1 1/2" @25yds. I also likes the Federal Auto Match which performed well but the groupings werent as good (could be the shooter).