Everything that you need to know is posted here, start with the cleaning and lapping sticky at the top of this forum list. The bore will take 150-200 rounds to settle down if you don't lap the bore first, 50-100 rounds if you do lap it. Shooting when the barrel is hot or the weather is hot doesn't help, you need to take your time and shoot with the barrel as cool as possible. Be patient and give it time, it will work out. The front rest needs to be under the hinge, that has been stated a million times here, it's pretty much true for any break barrel rifle, some aren't too picky, most are.
Hang in there, :wink:
Tim