In 1775 many Americans were members of clubs called "militia" that met a couple times a year for training. These militia men carried their own firearms and made their own bullets because the states and Congress didn't have the revenue to pay for them.
That's why in 1789 when Congress added the bill of rights to the constitution it included the Second Amendment. The Second Amendment to the United States Constitution reads:
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
Unless you believe that the Founders' knowledge of grammar and sentence structure was suspect (and what right-thinking person would think that?), the Second amendment, though it does employ a peculiar and sometimes awkward construction called an "absolute," is actually a very straightforward call for the establishment of an armed militia when necessary. It has nothing to do with individual gun "rights" except in that context.
Second Amendment does not guarantee gun rights
Why in, 1787 when the Bill of Rights was written, did Congress not address the rights of individuals to own guns? Because in 1787, most Americans were farmers living in wilderness areas with bears, mountain lions, Wolves, and unfriendly Indians. No one would think to question an individuals right to own a gun. Even today, in states like Alaska, it would be unwise to travel in wilderness areas without a gun.
I am a Vietnam War veteran with with a ribbon for marksmanship with the M16 riffle.