One of the gator hunters set up on land to try to shoot a gator because someone had tore down all their lines. The guy was said to have been a sniper in the military and he actually had some very good advice for would be marksmen. He talked about how to control your heart beat when taking a shot. He uses a different method than I use but I'm sure what he does will work very well. I've heard it explained the way he does it before but I've never tried it. He lets his breath all the way out which leads to your heart not beating for a couple of seconds. That gives you plenty of time to take your shot. I just time my shots to go between times my heart beats. It works but it takes some practice to get a shot off at just the right time. Either way should improve your accuracy. Even the slightest movement of a rifle can translate to a miss on a long shot. And a heartbeat can make your rifle move especially if you're shooting from a prone position. Learning to overcome that can make a big difference in your accuracy and I actually heard a Hollywood production give you good advice on doing that. That's the really amazing part.