You might want to check the crown, to make sure that nothing has happen to it! Do you have a LDC on it, did you check to see if it is clipping! Might want to turn it a Quarter turn at a time to see! Also , it usually takes a few shots to reseason the barrel after cleaning! Accuracy usually is the first thing to go when my barrel gets dirty on all my 13XX & 22XX guns! All I do when they get dirty is use a piece of weedeater line and pull dry patches through the barrel! If barrel was good at one time it is still good, short of a damage crown, or losing power! You might have to try a different brand or style of Pellet! That is one reason I try to buy as many of the same lot as possible! Good Luck ! It can be a hair pulling situation!.....John
That last group looks like one I had when I finally figured out that the windage adjustment on my cheap Centerpoint was not holding.I verified my problem by holding my rifle down on an immovable surface......then tapping on the turrets while looking through the scope. You could watch mine scan across the horizon. Once it got to where it was going, it would usually stay there for a short while......then I would crank the turret to fix the POI and things would start all over.Mike
Also, make sure you do all this work at a work bench or kitchen table, with a nice white towel spread out under it! You will have to take the the screw out of the trigger to remove the grip frame from the tube! Be careful , there is a little detente spring in there and a 3/32 safety ball, that like to go flying into never, never land! If you loose them, don't worry, you can salvage a spring out of a Bic lighter and cut it to length! And for a ball you can salvage one off an old key chain, until you get to a bicycle shop or order a hundred off of EBay for $5 . Just go slow and easy, you can do it! While you have the grip frame off would be a good time to smooth up the trigger sear, hammer and trigger! If you haven't already done that! ...if you need any help, just ask? We are here to help! Good bunch of guy's with a lot of knowledge! We all have to learn! Every body can't be an Old Salt!......John