I have a 319 bull on my wall that was killed with one 160 grain bullet from a 6.5x54. When cutting it up, I found two .243 diam bullets in the strap muscles along the spine area. From the fibrous track, I would say shot at going away, uphill. 243 Win or 6mm Rem essentially intact, weighing about 85 grains each (90 grainers). I believe that elk would be on someone elses wall if they were using a .308 and a strong bullet. People certainly do kill elk with a 243, but I believe a 308 Win is a more reasonable minimum for most hunters..............................FWB