The rifle's fore-end is just resting on a small sand bag contained in the front mechanical rest. That is why benchrest rifles have flat fore-ends. Large aiming errors are corrected by setting up the front rest (raising, lowering, side to side) till you are closely aligned to your target. Fine aiming is done by manipulating the rear sandbag or pinching the "rabbit ears" on the rear sandbag. The butt is rested against the shoulder and the hand is around the pistol grip with the trigger finger on the trigger.So I am guessing that all aiming adjustments are done at the mechanical rest end?
There are a lot of other factors to be considered. Your hold must be consistent, especially with centerfire rifles because you do have recoil to contend with. You must be able to control your breathing and you must know how to run a trigger without moving the rifle. However, these are just basic rifle shooting skills.
After that you have to be able to read mirage and thus wind speed and direction. You have to know what your rifle will do in different temperature, pressure and humidity conditions. You have to know what a five mph wind will do to your bullet at 100 yards, 200 yards, 300 yards, and so forth. You also have to know what a 10 mph wind will do at all these distances. What will a 15 mph wind do? Now shoot into the wind and everything changes. Shoot with the wind and everything changes again. Remember that the wind could come from any of the 360 degree points of the compass. The permutations and combinations alone can boggle the mind. You will have to figure out all this before each shot.
You also have to have the skill to reload a round so you get a consistent velocity out of the barrel with a minimum of shot to shot variation. For some of those guys it is more art than science. They have the scientific knowledge but can build upon that to produce a load will give them the best velocity and consistency for the particular load and the rifling twist in the barrel. Then by the time you have all this figured out, your barrel is shot out and you need to get a new barrel and start all over again.
You will have to shoot so much that eventually a lot of this can be done instinctively. So you can see that even with the gun held with a modicum of stability, there is still a lot to do. Given Bruce's rifle and ammo and rests, many people will have trouble doing what he did at 50 yards.... forget 600 yards.
That is why I was so excited about this group and also Baljit's 1000 yard shooting. Unfortunately, many people on here didn't seem to appreciate the feat and lack the knowledge to know what actually goes into making a group like that. In Baljit's case, he was using a commercial off the shelf rifle and run of the mill optics (compared to what is available out there) to do it.
You cannot discount the human factor. In the end it is the rifleman behind the rifle that makes the shot.
