IT'S ALL DEPENDENT ON PHENOTYPE AND STRAIN. YOU CAN'T JUST BUY BIG BUD AND GET ALL BIG BUDS. IT'S NOT THAT SIMPLE UNFORTUNATELY UNLESS YOU'RE BUYING A CUT/CLONE FROM SOMEONE THAT HAS DONE THE MEASUREMENTS AND CALCULATIONS.
The biggest buds are achieved by 600+ watt lights and co2 supplementation of 1200-1500 PPM so unless you can do those 2 things in your grow don't expect big nugs from any strain.