Thanks B.B. any idea why the 7828 has proven less than optimal with Nosler brass? Have you seen H1000 fail to shoot well before?
I've been running H1000 now in a couple of dozen different rifles since I ran out of my last jug of H870. I have yet to find a magnum rifle or caliber that I couldn't get a good accuracy load for using H1000 but it does tend to run slower than RL 23, 25, and 26.
RL 26 tends to run considerably faster than all of the other powders I've compared it to and the only caliber I've tried it in that I wasn't completely impressed with was the .260 as there just wasn't quite enough case capacity. I did find loads for the .260's though with it and several different bullets that were exceptionally accurate and more than fast enough to get the job done but I was basically running a completely full case of it and highly compressing the loads so I moved to RL23 and then 19 as my "happy places".
Before you go too far though with your loading, back up and check the basics.
Make sure your rifle is completely free floated, if you haven't bedded it, do so, and check the torque specs for the the trigger guard screws and ensure they are properly torqued.
Also make sure your scope mounts are properly torqued and solid and that your scope is correctly mounted with no movement.
It's real easy to drive ourselves nuts tinkering with loads chasing elusive accuracy only to find out that one of those things is causing an issue especially with a rifle we haven't used in many years.
In fact, it might not hurt you a lick to give the bore an extremely thorough cleaning with an emphasis on decoppering and making sure you don't have a carbon ring building up/built up just ahead of the chamber.
Also I've found that Nosler brass is often thicker than the old Remington brass which can significantly impact your case capacity and pressures so that might be part of your issue.
All of my Stw's have shot the Accubond, Accubond LR and Hornady Interbond quite well and Hornady has the Interbond back in production.
Also check to be sure what your twist rate is, if you decide to shoot anything heavier than the 160-170gr class of bullets you're going to need at least a 1:9 or faster twist rate and few of the older production STW's have better than a 9 twist.
Welcome and have fun, you'll find the STW has a tremendous following here and there's more good advice available right here than you are likely to ever find anywhere else.