Most bullet manufacturer's publish the """recommended" ft-per seconds to get the best expansion from each bullet... I would think that they are testing them in the flesh department...
Its a good place to start your research from thier Web site to find out...
Here's an example of what Nosler recommended for the 6.5 140gr Nosler Partions...
Excellent expansion from 2300 ft-per seconds on up,,, minimum at 1800 ft-per seconds,,, so I capped it off at 1900 ft-per seconds to allow for a fraction of lee-way...
Of course there is always a catch 22 when it comes to shot placement and how the critter takes the hit...
Look up some of your favorite hunting bullets and see what they can offer for expansion,,, the 50/50 rule to find out if they will suit your needs...
Cheers from the North