[wildhobbybobby]

Well, let me put it this way...in a former life as a law enforcement officer in a very rural area, I used an AR-15 quite a bit on dogs chasing and killing deer , and also on deer that were injured by cars and dogs. Many of the deer were still able to run and had to be tracked down to be put out of their misery. Most of the ammo I used was handloaded with the Hornady 55 gr. FMJ. It was extremely effective and I could not tell any difference between it and the military bullet (or any expanding bullet either, for that matter) on live targets. The Hornady was not quite as streamlined as the military M193 bullet but it was accurate and never lacked for punch on animals up to 200 lbs. Personally I thought it fragmented just as well as the M193, but I never did any autopsies to find out for sure.

 

[wildhobbybobby]

Actually the M193 military bullet does fragment at velocities over about 2700 fps in living tissue and ballistic gelatin. The bullet yaws after about 4" of penetration and breaks into two large pieces at the cannelure (there are many small pieces as well). That is the mechanism that gives it such good stopping power, because it creates a very large volume of destroyed tissue.. In short barrels this effect is diminished or may not occur at all, in which case the bullet will yaw and penetrate base first in one piece, making a much smaller wound track. Also, as range increases beyond about 150-200 yards and velocity drops below 2700 fps, the fragmentation effect disappears even from longer barrels.

Here is an illustration of this subject:

http://www.firearmstactical.com/pagea18.htm