17 rf vs 22 rf ammo price

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What's the reason for price difference in ammo?

 

[B23]

All of the different 17 rimfires use either an alloy or copper jacketed bullet where as all of the 22LR bullets are either lead or have have some kind of coating on them so I'd imagine some of the cost difference is in the bullets as well as the 17RF's take more of everything, compared to a 22LR, but probably the biggest difference is in the sheer volume of 22LR made compared to all others combined and that alone likely drops the price per unit well below anything else.