▁Act ▁and ▁fire ar ms ▁manufact ured ▁with ▁specific ▁features ▁are ▁subject ▁to ▁restrictions ▁and ▁controls . ▁In ▁the ▁case ▁of ▁a ▁vertical ▁forward ▁g rip ▁on ▁a ▁p istol , ▁the ▁law ▁does ▁not ▁explicitly ▁define ▁such ▁a ▁feature ▁as ▁belonging ▁to ▁any ▁category . ▁ ▁In ▁May ▁ 1 9 9 3 , ▁in ▁response ▁to ▁legal ▁action ▁brought ▁by ▁the ▁Bureau ▁of ▁Al co hol , ▁Tob acco , ▁and ▁Fire ar ms ▁( AT F ), ▁the ▁South ▁Carolina ▁District ▁Court ' s ▁finding ▁of ▁fact ▁concluded ▁that ▁a ▁p istol ▁modified ▁with ▁the ▁addition ▁of ▁vertical ▁fore ▁g ri ps ▁was ▁still ▁a ▁p istol ▁and ▁not ▁any ▁other ▁weapon ▁device . ▁Following ▁this , ▁the ▁A TF ▁dropped ▁their ▁charges ▁and ▁the ▁case ▁was ▁not ▁tried ; ▁as ▁such ▁no ▁preced ent ▁was ▁set . ▁ ▁In ▁an ▁open ▁letter ▁sent ▁to ▁Federal ▁Fire ar ms ▁License es ▁in ▁April ▁ 2 0 0 6 , ▁the ▁A TF ▁stated ▁their ▁interpretation ▁of ▁the ▁law : ▁that ▁installing ▁a ▁vertical ▁forward ▁g rip ▁on ▁a ▁hand gun ▁is ▁the ▁same ▁as ▁manufact uring ▁an ▁Any ▁Other ▁We ap on ▁( A OW ) ▁category ▁fire arm ▁and ▁subject ▁to ▁registration ▁and ▁tax ation , ▁with ▁significant ▁pen alt ies ▁for ▁manufact uring ▁or ▁possess ing ▁such ▁an ▁un register ed ▁weapon . ▁ ▁The ▁A TF ▁has ▁stated ▁that ▁ang led ▁g ri ps ▁do ▁not ▁make ▁an ▁A OW ▁from ▁a ▁hand gun . ▁ ▁See