There is so much erroneous with your post. I will try to respond to each point, but suggest that your verify.
Automatic guns (machine guns) were not illegal in 1970. They are not illegal today. See Fire Arms Owners Protection Act.
https://www.washingtonexaminer.com/...-extremely-difficult-and-especially-expensive
"Assault weapons" is a matter of form, not function. The difference between an evil black rifle and a stock semi-automatic AR is primarily in mind set/attitude.
The type of guns we own is not a matter of need but more likely what we want and can afford.
Hunting/bag limits are set by the individual states - frequently more than one per season.
Semi-automatic rifles similar to the semi-automatic AR-15 have been used in high-profile and deadly mass shootings over the years in Aurora, Colo.; Roseburg, Ore.; San Bernadino, Calif.; Newtown, Conn.; Orlando; and in 2017, Las Vegas and Sutherland Springs, Texas.
None of the guns were full automatic/machine guns.
http://www.politifact.com/truth-o-meter/article/2017/nov/08/facts-mass-shootings-united-states/
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