Going to have to agree with pus on this one. 3/4 an acre isn't that much land.. Could be easily seen by others. And the kid is going against our advice, and not realizing all of the real safety hazards there will be, especially if he does a half-assed job of building the stuff (which is easy to assume since he is a kid and probably doesn't have the funds or the inclination to do a proper job on this stuff).
And where did he and his friends get his guns in the first place? We shouldn't be condoning underagers buying guns and then playing with them in a backyard.. This is what ASC has been opposed to for years! Why change all of a sudden?
I am not flaming the kid, but I am going to say what everyone else who agrees with me is saying.
Wait until you are 18, and go out to real local fields with real airsofters and they can teach you the right way of doing things. Even once you are 16, I bet some of the fields will let you come and play with parental supervision/participation. But for now, many of us here at ASC are not going to condone kids who are under 18 making their own unsafe fields in their backyard, and then having them and their friends play with it (probably unsupervised) with guns they shouldn't have been able to get.
I love freedom and consequently America