The AR 15 and M 16 are chambered in 5.56 mm or .223 caliber. Essentially the same bullet and it is the same projectile. So, the question is; which causes greater damage? A bullet from an AR15, a Ruger Ranch rifle with the same length barrel, a Remington bolt action with the same length barrel or a Thompson-Center pistol(or rifle) with the same length barrel. In all cases the barrel length be 16 inches.
Just so you have a frame of reference:
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