Double eagle mws mk18 12.5"

DE MK18 gbbr never fielded Stock internals，only has tiny scratches on the rail. After market muzzle，1x tan gunsmodify magazine I tried to fit a feda npas，it did enable adjustable FPS but reduced the stability at full auto，so I put the original valve back. Currently shooting 320FPS with 0.2g bbs，750 rpm The feda npas Will be included Want to sell either this or the hk416 Collected from coventry preferred but can ship for extra