I couldn't find any info on MN receiver material. Supposedly its fairly soft and unlikely to blow up under heavy loads - expands instead.
But the MN has some problems that make me keep it in original military configuration and would stop me from spending much money on it:
The bolt handle is too far forward for fast, easy manipulation.
The split bridge makes it hard to install a conventional scope and side mounts are less efficient.
The safety is poor.
I believe there's only 1 trigger mod available.
The external magazine makes the rifle clumsy to carry on a hunt.
Gas handling/protection provisions are mediocre.
The WWII Soviet rifles are poorly finished.
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