One major difference is the polymer tipped ones Don't ricochet and the dimpled/hollow points do. They were designed specifically to be used in built up areas and not ping off somewhere.
Had 3 different branded rifles in 17hmr so far and each one preferred different ammo. Both will kill bunnies and goats but the 17gr polymer tips are more explosive on bunnies and have less penetration on goats,whilst the 20gr hollow points are almost the opposite ie you can still actually eat the bunny and the goats go down fast.
Found hornady and cci the best accuracy wise, then federal, and Winchester dead last,as in so bad id would rather go home from the ammo shop without it as you would actually miss.Something that Never happened with hornady or cci.
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