Im not sure about a grizz BUT I shot a WT Deer that weighed 337 lbs on the hoof with a 7mm08 at 165 yards ...shot it through the right rear hip (only shot I had) and it died of massive enternal injurys but bled very little ... I was shooting 139 grain Ballistic tip ... 7mm08 is a great cal. but I doubt I would ever want to hunt a grizz with one ....

Doc