BTDT83

Dan Newberry knows his stuff. You may also want to google "Ladder technique for load development." I use to burn through a lot of ammunition before finding the optimum load for my precision rifle. Using the ladder technique, it takes between 20 and 40 rounds. A good starting point for a .308 is a quality 168g projectile and 41.5g of H4895, H4064 or RL15 with a C.O.L. of 2.800". I could type several paragraphs on optimum C.O.L., but .2.800" has worked well enough in a few of my rifles that I did not change the C.O.L. until I saw a significant change in the free bore. I think it is a very good starting point.

Like M Gardner pointed out. If the line dissecting the bore axis and sight plane is not perpendicular to the ground, you will see a POI shift. If you are canting the weapon, try holding it with the sights level with the deck and see what changes. I like doing this while training, so I can mentally reinforce what happens when I cant the weapon. Close in it does not matter much, but at 25 yards and farther the POI will shift enough to make you want to pay attention to weapon cant.

I started shooting in 1968 and had my first formal training in 1978. I was a firearm instructor before I retired. I am still learning everyday.

I shoot with both eyes open out to 15 meters with a pistol and iron sights. Even quick headshots on a B-27 are attainable. I shoot with both eyes open out to 50 meters with a rifle using iron sights. I shoot a bit farther with both eyes open using an Aimpoint. I think it makes it easier to pick up movement and transition from one target to another.