I have been crossing in and out of Sonora for several years. I have been told by several CBP agents that they do not concern themselves with optics and there is no reason to list them on a 4457. The problem with CBP agents is one will tell you one thing and another will tell you just the...
You will be fine. I just came off a hunt where I helped guide two first time Aoudad hunters. We took two 30+" rams at 130 and 220 yards. If you are hunting west Texas, the country can be rough and stalks to reasonable distance can usually be done. Same old same old..it is shot placement.