You have a H&A that was sold under the Revonoc brand. Revonoc is Conover spelled backwards, Conover was the buying agent for Merwin & Hulbert, who distributed for H&A. A little bit of late 19th century humor in the name.
As noted before, you need to make a custom stock to use this as a dedicated schuetzen. The .25 firing pin will probably work with .22 rf just fine, if not, a new link is simplistic to make just a bit longer so the block raises enough to hit the .22 rim right. It's a thin piece of sheet metal with 2 holes in it. This action is one of my favorite .22 rf single shots. Nice and sturdy.
I would personally either rebarrel with a good .22 barrel, or if I relined, I would bore out the existing barrel to about 1/2 inch inside, and make a removable liner that slides in firmlly on teflon spacers. The virtue of that is 2 fold: One, the liner can be shortened to 15 or 16 inches for less barrel dwell time (better offhand accuracy) and two, the teflon spacers can be moved around to tune the liner to gain maximum accuracy. I've built 2 liners like that, and they have been the most accurate .22's I own. The one I have now outshoots my next 3 most accurate rifles, a 44 stevens custom, a Ballard custom target .22 with a Lilja barrel, and an Anschutz 64. And, that's in a rolling block with glacial lock time and a penny crushing hammer fall. I would recommend John Taylor of johntaylormachine.com to do the work if you don't do it yourself.
Good luck on the project. If you need any advice on the liner, I can post details (I have a thread already on that somewhere on here) and if you want to make a custom stock, I did a thread on here last winter on how to do that. I have a partially completed schuetzen pattern stock for a H&A Junior, but have been too busy to do any more on it this summer. Maybe when the winter gets here, I'll take it up again.
dave
PS: link to stock thread:
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