One of my more popular posts was Where does the bullet go?. I am somewhat of an expert on small arms exterior ballistics (I wrote Modern Ballistics) but while better than most people on terminal ballistics I usually refrain from saying much on the topic. Greg Hamilton and his colleagues at Insights Training are much higher on that food chain than I am. Although John Fogh doesn’t mention it I know a little bit about the research Insights has done on the topic over the years.
John gives us some of the research results on Terminal Rifle Ballistics.
Yup, and I for one certainly can’t predict which bullet will do what at what velocities at what twist, in which targets. I was fairly surprised, for example, that a pure lead (meaning soft, as opposed to the harder lead alloy bullets used in modern firearms) 0.495″ swaged round ball traveling at about 1850 fps on impact went clean through an adult whitetail deer, rib-to-rib, with no obvious deformation (judging from the entry and exit holes in the hide looking exactly the same). Maybe the swaged ball was work-hardened, compared to a cast ball. Dunno yet.
But we can make some educated estimates, and then test them (and what fun it is). Then there are bullets designed to do specific things in specific targets at specific velocity ranges with a certain rifling twist, and those results have been tested by the manufacturers and by others. These days we have it pretty good in that there are some very good bullets out now.