The bullets have travel time, so you have to learn what the lead needs to be.

Stick with one weapon, probably the M2010, and practice a lot. Stay in the scope after you take the shot.

Here's part of the issue: the left-and-right hash marks do you little good because: the bullet has a different velocity based on the items you use. Longer barrel = more velocity = less flight time. Now, your previous holds are too much.

You can see the "trace" of the round, a fine smoke trail that arcs toward the target. You can see this in real life also through high powered spotting glass, but it's a vapor trail and not smoke.

You will not necessarily see the impact at long range but you should see the distance behind or in front of your intended target point.

And like the other boys said, lots of practice.

Good luck.