Horetore, you mean well, but these types of efforts, in the context of the USA and its culture, are a little silly (albeit well-intentioned).
With more than 275 million firearms in private posession and with a full third of the US population in posession of guns, they are a nearly ubiquitous part of our culture. Firearms account for roughly 32,000 deaths a year (including accidents) in the USA.
As a side note, we have roughly 300 million motor vehicles in the USA, with over 90% of these in private possession (with 2/3+ of the households owning a vehicle) and roughly 35,000 deaths a year in motor vehicle accidents of one form or another.
Unlike a car, however, firearms only serve as weapons.
Magazine capacity size etc. isn't quite like re-arranging deck chairs on the Titanic, but....
To make a real difference in gun violence you would have to either 1) start confiscating firearms (Good Luck with That), or 2) start to address the cultural issues/mores/etc that are the cause of the violence for which guns are only a tool of expression.
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