Congrats on your purchase. .22 magnum is not the most accurate round in the world. Do not dismay, buy several different types and brands of ammom use sandbags and a bench, and do your best shooting.
I own a #650 and it likes the 33 gr. Remington ammo the best. Of course it would, as it is also the most expensive.
As many others have warned, this will be loud and ear protection is necessary.