Technical data

TM 9-1005-319-23&P 0015
0015-20
ASSEMBLY - Continued
M16A3 & M16A4 RIFLE/M4 & M4A1 CARBINE ONLY
NOTE
Failure to install barrel stop assembly will prevent the M203A2 launcher from being
mounted to the M16A3/M16A4 rifle.
7
8
1 v s 1 0 4
Figure 27. Installation of Barrel Stop Assembly.
19. Install barrel stop assembly (7) to barrel assembly (8) (M16A3/M16A4 Rifle only). Place barrel stop
over thin section of barrel from six o'clock position, while avoiding contact with gas tube. Rotate barrel
stop so opening is pointed upwards toward gas tube. Slide barrel stop forward until flat vertical
portion fits into triangular sides of forward hand guard cap with springs to rear.
4
1 v s 1 2 6
2
5
2 8
1 9
Figure 28. Installation of Upper Handguard Assembly (M16A3/M16A4/M4/M4A1).
20. Loosen slotted screw (4). Orient upper handguard assembly (5) so rear-locking clamp (28) is hanging
down, after confirming that arrow on its inner surface points toward muzzle of weapon. Insert front
end of upper handguard assembly into forward handguard cap at an angle. Be sure leaf spring at front
of handguard assembly fits inside lip of handguard cap.
NOTE
M16A3/M16A4 RIFLE ONLY: Ensure notches at front edges of upper handguard
assembly engage tabs at rear edges of barrel stop as handguard assembly is engaged
and lowered into its final position.
21. Compress rear handguard slip ring (2) and pivot upper handguard assembly (5) down into fully locked
position around barrel nut. Ensure that gas tube slot of rear-locking clamp (28) is straddling gas tube
and that rear legs of clamp slip under barrel nut flange as handguard assembly makes contact with
barrel nut and slip ring.