It actually causes a rise in muzzle velocity . Trapping gas means higher pressure . The biggest disadvantage is probably gas getting blown in your face near the charging handle . Need an adjustable gas block to correct that . <| sep |> This is a legit solution . <| sep |> Ummm I already did and every single source I ' ve seen says 441 . 6 . So not sure where you ' re getting 600 . He ' s also borderline obese . <| sep |> My boy is not so dainty . He would plant his face if he could . I had to get a special bowl that forces him to drag out his food piece by piece in order to slow him down so he wouldn ' t overeat . He ' s better now than he was , and at least he ' s not overweight anymore , but if I ' m not watchful , he ' ll literally eat until he barfs .