I mentioned this in a another 10/22 mag related thread, but with my 10/22, both the factory 10 round rotary mag, and the HC3R had many issues. Primarily, when the bolt would come forward to try to strip a round from the mag, instead of the nose orienting upwards, and sliding forward, it seemed the round would come forward, maybe even tip downward slightly, and then get hung up at the front of the feed lip, instead of sliding up the feed lip.
So the first 3-5 full loads run through both mags had issues. But after about 5 cycles of fully loading, and running through the 10/22, both mags now run pretty flawlessly. I keep a log of every round fired, the ammo, the conditions, where the ammo was bought, when it was bought, how many FTF, FTE, etc. And I could not get through a single mag without at least 1-2 jams per load for the first 3-5 cycles. Since then, it's been less than 0.5%. In fact, hitting 2 "duds" out of a single pack, oddly enough back to back (out of a box of Winchester 333, where the pin left a noticeable dent in the rim, I even cycled and tried hitting it again and still nothing) have been the most notable failures since then.
I even had problems with the ammo not sliding up and down the HC3R with the spring pulled back initially. But I think wax deposition from the ammo, and a combination of light scuffing/abrasion typical of use, in a sense "broke in" the mags.
For those of you that had all these problems, did you eventually get enough rounds through them to get past that break in stage I observed?