A bewitching question. Since the JW25A is based on the Brno Model 2 which later became the CZ 452, I would say the 452 magazine is the one you're after. Of course the CZ452 magazines are interchangeable with 455 magazines -- at least they are with mine. It's possible that earlier 452 magazines were exclusively metal, whereas now the five-shot ones that accompany new rifles are polymer.
