There is a .17-.223 wildcat, then google the .17 incinerator and the .17 incinerator improved.
That's not all, you can go smaller than that. Here is a partial list.
.10 Eichelberger LR .12 Eichelberger LR .14 Eichelberger LR - original Eichelberger load .14 Eichelberger LR .17 Eichelberger LR .20 Eichelberger LR .12 Eichelberger Magnum .14 Eichelberger Magnum .17 Eichelberger Magnum .20 Eichelberger Magnum .14 Eisenburgh .14 Eisenburgh Magnum .14 Kopp Short Case .14 Kopp Long Case .14 Hornet .14-.22 OTTR .17 Myra Minor Mite .17 Myra Vixen .19 BN Short .19 Wildcat
