.223 75 grain A-Max
Below are pictures of the 75 grain A-max, fired from a .223 rifle which yielded a very fast 2950fps. Ranges were between 150 yards and 250 yards (several goats were shot). Body weights ranged from 25-45kg (55-100lb). The results were the same throughout, massive internal wounding yet the animals still ran a long way. The hunter was quite surprised to find so much internal damage after such long 'dead runs'. It was not without a level of disappointment, the hunter noted that in bluff country, animals would easily be lost after running and falling off ledges.
The massive internal wounding is obvious. Note the rumen fiber (grass). On cross body shots, this occurs when the chest is expanded to the point of rupture, then collapses. The vacuum is so great that rumen fiber is drawn from either the esophagus or gut into the vitals. In larger calibers when this type of vacuum occurs, it can draw the rumen fiber between the offside skin and muscle (a big lump of grass inside the skin). In either instance, tainting of the meat is a problem. A change in bullet design can prevent this effect and the associated tainting. This effect is somewhat unique and can appear in any cartridge combination with certain loads and certain game weights or certain range parameters.
The hunter also found that the cheap Barnaul 62gr HPBT gave faster kills. The Barnaul projectile is made of mild steel, copper washed. From my own experience, the Barnaul bullets tend not to expand on impact but instead tumble. Even after tumbling, it is common for near 100% weight retention. This leads to deep penetration and quite often on light game, exit wounding. Exit wounding in turn prevents blood clotting in the vitals for fast bleeding. Fast bleeding prevents blood from being locked in muscles. This robs the muscles of oxygen (fuel). So while both the .223 A-Max and Barnaul produce adequate (or dramatic) internal wounding, the Barnaul can remove blood faster from the muscles. Death can occur within several seconds as opposed to (for example) 15 to 20 seconds, the latter being enough time for a mountain animal to make for a bluff. This is why I prefer cartridges and bullet weights that produce exit wounding if possible.