I have been to two underground testing ranges in my life. One of them was at the Hornady factory. These two factories used barreled actions in vises for their shooting. So basically they were shooting a particular rifle. When they indicate the most accurate load-they are indicating which load is most accurate in their particular rifle. And as you know each rifle is different.

They may be testing their bullets differently now. It has been over 15 years since I have been there. But that is how they used to do it. It could be different now. Tom.