I'm looking at either buying a 4x16x50 or 6x24x50 Vortex HS model with the BDC primary use will be for hunting. Wanting something that I can see good in the 300-500 range. After doing research and reading several forum post my understand is that on the 4x16 model the scope would need to set at 16x power to use the bdc marks. The user manual for the 6x24 model says it needs to be set at 18x power. I would prefer to have the scope power maxed out while shooting. Due to this I'm leaning more towards the 4x16 due to having it maxed out and using the bdc mark. Not sure how I would calculate the 6x24 if I was using power turned up past 18x?