"Why do people not use premium bullets?"
Because bullet placement is more important than bullet construction. Not all game animals need a premium to kill them, and some rifles might shoot a standard cup and core hunting bullet more accurately than a premium bullet.
I now hunt almost exclusively with premium (Barnes TSX and TTSX) bullets in my .375 RUM and my .300 Weatherby.
But I haven't always and still don't always use premium bullets for certain game animals or in all of my hunting rifles.
Here are some (high dollar?) animals that I made one shot, DRT kills on with standard cup and core hunting bullets...
A 375" bull elk from a DIY public land hunt in Montana with a 180 gr Sierra Gameking bullet from my .30-06.
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My first Montana Bighorn from a DIY Solo hunt with a 117 gr Sierra GameKing bullet from my .257 Ackley
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Another Montana Bighorn from an Unlimited unit, also on a DIY solo hunt with my .257 Ackley and a 117 gr Sierra GameKing bullet.
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Another Montana Unlimited Unit Bighorn ram from an Unlimited unit, also on a DIY solo hunt with my .257 Ackley and a 117 gr Sierra GameKing bullet.
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And this Northwest Territories Dall ram from my first guided hunt, but also shot with my .257 Ackley and a 117 gr Sierra GameKing bullet.
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