The .22 Hornet is one of the favorite Handi Rifle caliber over at Graybeard's which has a devoted NEF/H&R membership that identify themselves as "Handi-holics".
The .30-30, .357, .44Mag and .45-70 all are supplied with opens sights. I believe the newer .45 colt Buffalo model is as well. Best to check the NEF web site for details.
All those calibers are considered the calibers most suited to the Handi rifle. The Handi rifles are capable and regularly shoot very well. Many, myself included, have several examples that will shoot consistent MOA. Some are capable of sub-MOA.
Some of the more accurate are the .223, .7mm-08, .270, .280, .30-06 just to name a few.
They are a tinkerers dream. There are many quick and easy ways to accurize them.
I have several Handi/Ultra rifles, including rifles in each of the aforementioned calibers. They all shoot very well.
I recommend that you check out the Handi forum at Graybeards and read the FAQ section. It is extremely detailed with just about any info you may want regarding the Handi rifle.
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