I'm incredibly mediocre at dive bombing, but the biggest thing that helps me is watching the dive angle. At least 70°, and preferably 80°, will get you quite close. Make sure the ball is centered (no slip or skid) and your wings are level (look through the up or up/forward view and make sure the horizon is level). And no G loading! Pitch should be centered, or very close to it, when you release.
Start your bomb run at least 8,000 feet above the target. That should provide enough time to get the parameters right and still drop at 2,000 AGL or better. As you get better you can change the angle and start altitude and still get hits.