Looks like a nice pistol/carbine. How do you like that Cleavercraft mount? Stable? I've never heard of it before.
Regarding sighting in at 30 feet and shooting at 60 feet and expecting the same zero - I'd expect the pellets to be on paper, but probably an elevation change would have to happen.
I use the little Crosman barrel mounts on my 1377 with a rimfire to weaver adapter to mount a Bushnell red dot. I had to shim the mounts at the pump tube to try and eliminate mount wobble. Even then, it can still move if you bang it around just a bit.
All I do with my 1377 is 10 to 15 yard pistol practice.
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