I’m not sure of the manufacture I think I still have the paper work on it but I am still at work. I will look for it after I get home, I did buy it from the manufacture and I have put about 100 rounds thru it. MOA built into the scope base and how the chamber was cut no idea lol, Sorry As for the lower holding up I had the same concerns so every time I took it out I would inspect both pins and looked for wallowing on the pin holes it always checked ok. The break dose a great job (just don’t stand to the left or right of it ) it don’t kick as much as you would think, Its just a big heavy useless toy, man it is fun to shoot. I’m told but not sure you can shoot in at Spring Valley don’t quote me on that. My local range band them last year, I shoot it at bullet fest and down at knob creek.