Is make sure the stock screws are tight . The front trigger guard screw s'be tight ,the rear snugged down but not real tight. Clean the barrel internally with a springer safe solution (Simple Green,GooGone 'Fabtastic' Beeman MP5 etc) NO Firearms cleaners!!! I use a pull thru type cord to clean , others will say a coated rod is fine .Either way take care of not messing up the barrel crown . A few dry patches follow the cleaning patches . Wipe down the metal with a good protectant - sorry folks I use Beeman MP5 here. I know it works and I have some . Shoot, enjoy !! After you're done wipe down the metal work again and check the stock screws . Don't worry about cleaning the barrel but every 500-1000 shots . Hope that helps , I'm sure you'll hear more about this as time goes on . Afterall I b a Noooob 2 .
I would add, familiarize yourself with all the mechanics of the 48. It is a different airgun from a springer,
I love my 48, It has a different feel and recoil, powerful and at the same time easy to tame. I have the .22 cal and it is a joy to shoot. You might find some pellets are more difficult to insert than others but you will get the "knack" for it (more so in the .177).
and remember "it's 30% the gun and 70% the shooter"