yukon, I have shot several antelope with factory WW 150 gr. hollow points from my Marlin .30-30..it has a 24 inch barrel with half mag..so vel. may be higher than from a 20 in. barrel..I may have shot deer but off hand don't remember, and don't have my notes handy..the hollow points are real killers, but they do open up much more than Silvertips..the last antelope I shot with my 30-30, I left the house with the rifle and box. of WW shells...when I went to load the gun in the field they were hollow points..dropped the antelope fine, but did do much more damage than the Silvertips..