You have an excellent scope for your rifle, so (assuming you know how to use it) parallax shouldn't be a problem. (Many .22 "accuracy" complaints turn out to be actually parallax problems.)
Make sure all your screws are good and snug, including the scope mount screws and all the scope ring screws.
Then try as many different ammos in it as you can find. Start with the cheapest and work your way up the price scale. When you find the ammo that's delivering accuracy that YOU consider worth the money, you've found your ammo. (This can occur at any point on the price scale, which is why you start with the cheap stuff.)