I started with a cmmg conversion (bolt) kit dropped into a colt m4, so could participate in rimfire rifle steel challenge. This was just “ok”: so-so accuracy and too heavy to compete with various lightweight 10/22 customs. Plus, became apparent that a c-more sight was a clear advantage, so wanted one of those, too.
Next was a dedicated AR build using spare parts, said ccmg kit, and a proper rimfire barrel, turned to .625 (pencil contour) and cut to 16.1 inch (ADCO gunsmthing). And a c-more; you’d need the ar railed base version. I had no issues with geissle or usgi triggers, but was advised that for these rimfire kits, the extra hammer oomph of a Hyperfire trigger aided reliability. So i’ve got one, still don’t care for it, has a different, heavy, crunch of a pull. May not matter under recoil of centerfire, but it’s “different” feeling under rimfire. Might go back to a geissle just to see if reliability issues arise or not. Anyway, bang for the buck, this basic setup above is the sweet spot. Put whatever style stock and handguard, sights you find fitting for your kids and you’re set.
For just the cmmg kit, you’re at $225 iirc. For barrel, contouring, about $250 more. Beyond that, sky’s the limit of course. I kept tinkering, so now it’s gotten silly, i”ll spare you. Am a tad too light out front now. It is right fast, however, and good fun.
Couple thoughts. Kept halfway clean, the ar 22conversion consistently runs like a top. Was past 2000rds this summer, yet to have a single jam (!), when broke a firing pin. Plus, the magazines clean easily. I went with the aftermarket blackdog mags for the cast steel lips rather that cmmg’s plastic.