The best thing I ever did for my fundamentals was shoot 300 Norma Mag unbraked for a while. I’d say you are taking the right road.That I can do! I did a lot of dry firing at home setting up my rifle with the eye relief, cheek piece as I moved my position of the rifle from my shoulder pocket to my collar bone. It's adjusted where it all feels comfortable, and dry fired a bunch of positional shooting positions. I need to do what you say, put a pasty on the wall, line everything up straight, and pull straight back. I also need to get a more constant/repeatable position on my elbows that is holding the rear bag, so see how that might be causing my shoulders to shift. I'll get some videos dry firing so I can analyze... Thank you for your detailed response.
Shoulder pocket + Area 419 Hellfire Brake, I was shooting really well, and I was staying on target after every shot. Switching to collar bone + removing the hellfire brake, showed lots of problems. So I'm going to keep working on it until I get it right, then go back to the brake/suppressor. Thousands of rounds of rimfire unfortunately do nothing for helping with recoil management...
I’m not sure what those smarter than me would call “correct”, but for me there is minimal pressure on elbows. Balancing weight on elbows is tiresome and rigid and creates pivot points. I press my lower chest/upper ribs into the ground by flexing my back; basically a reverse sit-up. That makes a solid slab of meat thats connected to the earth that you can connect the rifle to. Watch in the video when I reach up to turn the side focus before the first shot. You can tell there is almost no weight on that elbow when I reach up and then back down.
I used to have a good bit of weight on both elbows and a good bit pressing down on the cheek rest. Those where my main connection points to the ground. Not good. Now my whole torso is connected to the earth and the rifle is connected to my body. With that connection, a good NPA, and just enough cheek pressure for that last bit of steady, things get much easier and more repeatable.