John, I have witnessed wounded brown bears do the same. I can remember numerous bears that were still alive and attempting to get up a long time after receiving multiple fatal hits from 375's and .458's. The bigger calibers tend to usually put them down a little quicker and keep them down a bit longer but some animals can seem Bullet proof. I had one aggressive boar that took three solid fatal hits from my 505 Gibbs before he quit getting up and coming for us and Kodiak guide Joe Want told me similar stories of incidents when he was carrying his 500 Nitro H& H Royal double rifle.
