Here we go..
No not legal for you to buy... yes your mom and dad can buy for you but TECHNICALLY you should wait.
shooting targets in the back yard
NO NO NO
do it and a neighbour sees and you could face an armed swat team. treat ANY airsoft gun as a REAL gun. you can't shoot a gun in the city limits and all towns have rules too
so in the back yard is NO defenately NO.... Seriously NO
that is ILLEGAL period and could get you SHOT.... Police may tell you to drop it and if you don't act fast enough may add an extra hole in you...
no one here shoots in their yard... (unless their yard is out of the city limits and out of view of any person --- basically an airsoft field)