Need Savage Striker 308 Load ideas

Hey guys, picked up a Striker last year and now getting around to work up a load for it. Everything is stock except I have added a Nikon EER scope. I have shot it with the previous Burris scope (needed an upgrade to the optics) and haven't found anything that groups anywhere close to 3" at 100yds. I have tried 150gn and 165gn bullets of various brands as well as Varget and IMR 4895. Now, part of the issue could have been the antique Burris that was on the pistol when I bought it. Just wondering if any of you out there reload for the same gun and if you have any good loads. Thanks for the help.

I use 46.0 gr Varget and 150gr hornaday sp #3031, Fed brass & CCI BR primers
I can get a 0.60" 3 shot cloverleaf at 100 yards with a burris 3x12

The .308 Striker I had would shoot 165gr Fed GMM into a 1.5 moa group. Handloads were no better but I did not keep as a Striker for long, so loading was a limited experience.

Anyway, with the short barrels they have would a faster power work better?