Yeah. Check your iron sights. I just received a 350M in .22, and the front sight was so loose it nearly fell off out of the box. Both screws on the rear sight are loose, and the rear one has rounded slots that prevent me from tightening it. Oh, and the stock screws were loose, too. All this before I loosed a shot.
dont fire light pellets, ever ... They will ruin the spring ...
Mine was extremely dry out of the box, cocking it made a horrible squeeky sound of the seal rubbing against the cilinder ...
Took it apart and applied a tiny bit of molybdeen grease behind the piston seal > smooth without smoking or dieseling
If yours is smooth, leave it alone ...
Try lots of different pellets, H&N barracuda's fit perfectly in mine and are the perfect weight and have pretty much energy even at longer distances ...
Altough its power is a bit overrated by the RWS importer (1250 feet per second, instead of the 1100 something by diana) it's still the most powerfull springer except for the Gamo hunter 1250 (< you dont want the gamo, trust me on this)
I ordered a Titan XS spring for mine, just for kicks and ill let you know how that flies ...