People who try and interpret noise as data, not me. Please read my posts more carefully in the future.
Thank you for proving my point. Perhaps I'll try that every night the next time I'm on a 5 day hunt...
Again, read my posts more carefully. I never criticized the OP, but I concur that I may not have tried hard enough to help him. He's got a lot of posts, and so I assumed my first post made my point, but I'll give it another shot, without graphs...
@NW Hunter. This all assumes you've got your reloading practices and shooting skills pretty solid...
If it were me, and you think you've found near the top end for pressure, then I'd load 3 rounds each from about the max, at about 1% increments down (in your case 0.4-0.5 grains). Perhaps 3 sets. This is to ensure you're truly well away from overpressure issues. Hell, leave them in the sun for a few minutes, just to be sure you're golden.
From here (assuming groups aren't crazy for some reason), choose a charge that sits 20 to 30 fps below max, then do a seating depth run, with perhaps 5 at each length. Go from 0.02 out in 0.3 - 0.4 increments. Or just load to maximum length for your mag or 0.020 off the lands, whichever is longest. In my experience long is best, if only for more powder capacity, but not always.
At this point, shoot a few smallish batches of your ammo to confirm you're getting the same results day in day out. 10 shot groups (too bad no LabRadar, as I chrony everything). Fix any problems in your system that you notice (confirm drops, ensure temp/weather stability, realize you don't have a spare rangefinder battery in the case, etc.)
You're now 100 rounds in. Only 50 more than if you ignore basic statistics and burn these bullets at the range striving to find "forgiving ammo" before even confirming if your rifle can shoot OK with "crappy ammo".
Now's the hard part. Go shoot. Carefully and purposefully. Spend your time trying to hit what you want, as apposed to keeping bullets in small clusters not quite in the X. That being said, continually monitor your system. Shoot groups, try different bullets, play with ladders, adjust your eye relief, etc. Shooting is fun. It's unlikely, but possible you'll find something special. And even if you don't, you'll know the rifle like the back of your hand, and it will put them where you want.
Just make sure your action screws are tight, and that you're not looking at a tree (one little cluster) and thinking it's the forest (pew...................................................................ting).