a generally tubular member is provided at one end thereof with securing means for detachably securing such member as to a pistol type firearm and to be generally aligned with the bore of such firearm , forwardly thereof ; the tubular member has aperture or porting means formed in a selected portion of the wall forming the tubular member whereby gases , generated during the ignition of a related bullet assembly , may escape in a generally upwardly direction thereby creating generally downwardly directed reaction forces assisting in maintaining the fired firearm stable and at least significantly eliminate the usually experienced sudden upward jump of such fired firearm .