Just so you know; a BB gun, a Pellet gun, and an airsoft gun are not the same thing.
Using anything other than an Airsoft gun for airsoft is megadumb.
Also, an airsoft 'sniper rifle' made to shoot 650fps will destroy itself very quickly, and yes you will go to the hospital.
Also, playing at your cottage probably isn't legal, as many rural municipalities zoned for recreation/ residential have very strict laws about projectile weapons and airguns of any kind, from slingshots to Daisys.
Please turn 18 and/ or start thinking about this seriously.