Charles Daly Zastava barrel 308 loads

[Jack]

OK, make sure the actions screws on the rifle are tight- not gorilla tight, just firm.
Check all the scope mount screws and make sure they're tight, too.
So far, what you KNOW is that Winchester 180 grain factory loads shoot reasonably well, and that handloads with Sierra 150 BTSP's and Varget do not shoot well.
You might have to try a different bullet or different powder- maybe the rifle just doesn't like that combo (it's not common,but it happens)
You may have a rifle that doesn't like 150's.
It is far too early to conclude the rifle is defective.
Were it my rifle, I would try a Sierra flat base or Nosler Ballistic Tip bullet, with Varget, Reloder 15 and Accurate Arms 2520 powders. It will shoot with one of those combinations, in all likelihood.