Sorry if this is a little broad and hypothetical or too legal.
Say I (as a company) (hypothetically) was to build a space gun, reasonably similar to the 7-incher here in Canada, but with a second stage (hybrid acrylic/Lox) and a bit more complex, and able to reach a good 400km orbit.
Besides not shooting it at a Cessna or landing the projectile in an apartment building or something, are the legal hurdles manageable for a very small company with little lobbying power? Would I have to get a temporary no-fly exclusion zone, for instance, and have a range officer with an "explode" button etc? Essentially, is this something that someone who isn't Elon Musk or Gerard Bull could legally accomplish?