The only way to stop a charging grizz is to bust his wheels. You can do a double lung shot on anything that walks on this earth and kill it; but it can take more time than you are willing to risk. The heavy, wide meplat bullets will penetrate when and where you want. Just remember that millions of buffalo were killed with 1200 fps lead slugs. A COWW bullet with a wide meplat will pentrate like a freight train, and contrary to popular belief, the faster you drive it, the less it will penetrate. Any 400-500 grain slug going 1300-1600 fps will do and end to end on anything you will want to kill in N America. Have a read of Garretts penetration tests.....heres the link
http://www.garrettcartridges.com/penetration.html you will be amazed at the results. I have one of the hammerhead rounds in a mold from Tom at Accurate with a huge Meplat weighing in at 420 grains without lube or gas check.. If I recall correctly they come in at 430 all done up. I have the utmost confidence in this round on anything I can tangle with in the Selkirk mountains where I live....and we have some very impressive bears here.
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