F
It seems to me that trying to make a rifle shoot by buying a box of factory ammo, and then switching to another kind of factory ammo, is going the long way around, and that buying ammo to get brass is a bit expensive. Buy some good brass, and the rest of the necessary components. I would say that if I were going to work up loads for the same rifle, that I would pick up a Lee collet die, a Redding body die, and a Forster seater. While that was all on its way, I would float the barrel, and bed the action, and check my work with a dial indicator. I would also consider what game I would be shooting (if that was my purpose) and probably pick a good 150 gr. bullet to work with. A 150 gr. Sierra Game King would probably be fine. Based on my experience with factory rifles, I would stay away from BTs until I had it working with FBs. I would also look into the trigger pull weight, probably replacing the spring, and readjusting, if the newest triggers have that feature. The other thing that I would look at is parallax, some perfectly good game scopes are not adjustable for this, and if I were using one of these, I would want to determine if it was possible to find the distance that the parallax was set for, after first carefully focusing the eyepiece for the sharpest reticle image, against a featureless background, based on brief glances between adjustments. Once my bedding and floating were done and verified, I would start my reloading by determining if it was possible to touch the rifling with a seated bullet,a nd if the resultant loaded round would fit in the magazine. If it was possible, but would not fit, I might still do my workup single loading, with OAL adjusted so that the bullet marked the bullet slightly (probably .006 to .010 longer than touch) to give the rifle its best chance to show me what it could do. and then if it would perform that way, do a two shot test for several different amounts of bullet jump, in increments of .005 (at first) and then refine from there. If the barrel is rough, I would probably clean copper with the strongest Montana Extreme product, being careful to patch it all out, and follow with a little light oil and some dry patches after that. Light rifles in calibers that kick, need to be shouldered solidly, and your rifle will probably do its best with the front bag a couple of inches in front of the action. Balance is not an issue, when you are holding the rifle. Don't pull down with your hold; it can cause vertical. Make darn sure that your rear sling swivel stud does not engage your rear bag at any time either before or during recoil. That should get you started.