.22HP started out in the good ol' US of A. The 5.6x52R was/is used in combination guns and kiplaufs (single shot break open stalking rifles). In all my time searching for things HP, I never stumbled onto a double rifle and believe me I've looked. I would love to see such an animal.

I'm still kicking myself in the butt for ignoring a BRNO kiplauf in 5.6x52R. Imagine that- a modern strong rifle with a .228 bore and fast twist to handle the long heavy bullets.

Add the .236 Lee Navy to the list. Commercially loaded ammo was available in the early 1900's.

I wonder if Newton/Savage was eying the success of the small-ish bored European military cartridges of the time- to whit, the various 6.5mm's.

Last edited by gnoahhh; 09/13/17.
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