Did it have the plastic magazine when you saw/bought it ? Or, was the rifle displayed sans magazine, and it was added to the package when/after the sale ?
Steyr boltguns have had plastic mags at least since they replaced the M-S rifles in the early 1970's, so if yours is having a problem feeding/chambering, I'd take a hard look at both portions of the magazine latch - the part on the mag, and the part on the rifle. One or both may ned replacement.
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