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Ramline made a plastic 25rd mag also, and someone made a metal 15rd mag for a short time.
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I have an Armalite AR-7 rifle, and a Charter Arms Explorer II pistol.
The Ramline 25 round plastic magazine was reportedly prone to breakage so they are rather scarce. Eaton made a 25 round "banana clip" steel magazine that can be occasionally found. Last I knew, Triple K still made the 15 round stick magazines. I've got at couple and they are no better or worse than any other metal AR-7 pattern magazines that I have. Which is to say, both sets of lips - the rear set that positions the cartridge in the magazine and the front set that is the feed ramp must be adjusted properly. The good news is the mag lips tend to be easy to bend into position, and the bad news is the mag lips tend to be easy to bend out of position. Handle your magazines accordingly. I don't have mags from every vendor, but to my understanding, the Henry, Armalite, Ramline, Charter Arms, Triple K, Eaton, AR Industries, others? mags all are to the same dimensional pattern.
As for ammo feeding, the Charter Arms AR-7 pattern firearms were notorious for needing to have the lower lip of the chamber entrance very lightly "throated". The Armalite probably is okay.
For ammo, the typically recommended cartridge is CCI MiniMag, 40 gr., copper coated, round nose. As well as that ammo, I've had good feeding using CCI 40 gr. AR Tactical.
Best of luck and enjoy.
MHO, YMMV, etc. Be well.