I've had one for quite some time, purchased from the CMP long ago. Mine is a great shooter, but I've always been plagued with the mystery fliers.
My rifle will consistently throw 1 or 2 shots while stacking up the others. Below is a typical 10 shot group @ 50 yards (front rest & rear bag). This behavior is seen with multiple brands on ammo, although some brands don't throw as wide a flyer. I even went so far as to mount the rifle in a fixture to see if it was me, but the same behavior was seen.
In my reading over the years, I've heard people claim these rifles were known to have tight spots in the bore. Since mine is more of a "fun gun" I've never really pursued getting a replacement barrel.
There was a guy named Ken Viani that made mounts for these rifles that are absolutely rock solid, but I believe he discontinued production some time ago though. BKL also makes mounts that work well on the M12.
Great rifles for the money though!
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