The Hornady SST is a wonderful bullet out of a 270/280 for game up to 300/400 lbs under 300 yds.
Lighting fast kills on deer or bear with proper shot placement for sure. However for larger game such as Elk and Moose ; not that you couldnt knock them
silly at 150yds with proper shot placement, I would probably lean more towards a Partition or AB if hunting them exclusively, and if Longish shots (over 300 yds) was a likelyhood; I would move right into the ABLRs. We have had numberous clients now killing 800/950lb Maine Moose with one shot kills
at 400/500 yds way out in bogs. The ABLR is a true
LR performer. I really dont think the SST would work as well on long distance shot on Elk or Moose, but I would suspect the same is true of BTs as well.
The SST is my go to bullet under 300yds for game up to 400lbs. So we call it the 3/4 rule.
The best deer bullet I ever used in a 7mm Rem mag was the Hornady 154 gr Interlock. This was before they came out with the SST. My hunting buddy and some others I know will shoot nothing but the 154 SST in their various case size 7mm rifles for deer.
Myself, I would unhesitatingly use a 154 gr bullet my in my .280 Rem to use as a middle bullet, to shoot deer and elk. The 154 Hornady Boat Tail Spire Point is stout enough to use it on large bodies deer, and average elk.
I would gladly light an elk up with it, even at some distance.
I used the 139 and 154 SST both in a 7 WSM with great effect on large Missouri whitetails. Most shots were inside 200 yds and they put them down with authority. IMR 4831 and 4350 were my preferred powders.