Safety & Maintenance Instructions
DDM4
®
/ DD5
®
MANUAL P 13
the bolt pushes the next round of ammunition from the magazine and thrusts it into the
chamber. Simultaneously, the extractor snaps into the groove of a cartridge case and
the bolt locks into the barrel. The hammer is now held rearward by the disconnector until
the trigger is released, causing the disconnector to rotate back, releasing the hammer.
Before the disconnector’s hook actually releases the hammer, the trigger sear surface
has rotated in front of the hammer notch so the hammer is held on the trigger sear
surface, making the rearm ready for another shot. Upon cycling the last shot from the
magazine, the bolt catch is pushed upward by the magazine’s follower, catching the bolt
before it travels forward, locking it to the rear. With the bolt now locked open, the user
can remove the empty magazine, replace it with a loaded one, and press the bolt catch
paddle to disengage the bolt catch and load a live round into the chamber (be sure to
follow safe loading procedures).
WARNING: THIS IS A SEMI-AUTOMATIC FIREARM AND IS LOADED AND READY
TO FIRE AFTER EACH SHOT UNTIL THE MAGAZINE IS EMPTY. TO UNLOAD THE
FIREARM, THE MAGAZINE MUST BE REMOVED AND THE BOLT CARRIER GROUP
MUST BE PULLED TO THE REAR BY THE CHARGING HANDLE TO EXTRACT ANY
REMAINING ROUND FROM THE CHAMBER.
4.0.1
DDM4ISR
®
SOUND SUPPRESSOR FUNCTION
The DDM4ISR utilizes a specially designed Integral Sound Suppressor (or silencer) to
reduce the noise signature, muzzle ash, and recoil of the discharging rearm. Upon
exiting the muzzle, a red projectile is followed by extremely hot propellant gases and
unburned powder exiting at a very high velocity. This phenomenon is the cause for the
loud muzzle blast associated with the discharge of a rearm. With the use of a sound
suppressor, the muzzle blast is effectively contained and controlled, resulting in more
gradual pressure reduction and a subsequently less violent muzzle blast. In addition, the
design of the DDM4ISR fully integrates the suppressor with the barrel and gas system
of the host rearm. By doing so, a larger interior volume can be exploited to reduce
back pressure that would otherwise force more fouling back into the rearm’s barrel and
upper receiver. A proprietary gas block has also been incorporated to allow functioning
of both supersonic and subsonic loads without any additional modications to the action
of the rearm.