Impossible. The US highways leading into Mexico are clearly marked with warning signs, including State 77 in Texas. Get about 60 miles or so south of Corpus Christi and you will begin to see these signs. Do not bring firearms or ammunition into Mexico. Penalty is imprisonment. Large black letters, impossible to miss! As you approach the border between Brownsville, TX and Matamoros, Mexico, the signs are at more frequent intervals along the road. There is no excuse. This guy is a moron and is going to have an extended inside view of the dangerous and corrupt Mexican prison system! US State Department weenies will not be showing much support for him!