I picked the lowest mount for my scope and only have a 1" tube on a Vortex tactical, 4 x 12 x 40mm, I like to keep scope close to barrel....this is different than I do on my 6.5 creedmoor and 6.5 PRC, both of those have 30mm tubes and 56mm objective. The balance and weight on this set up on my CZ is really comfortable. The 39 grain SBK bullet has a BC of .287 @ 3600 fps and higher, which is high for a small caliber bullet. This is an aid in wind drift, my opinion. I like to know all the details on stuff and look for every advantage I can....could be that 1/2 of Germanic blood in me.