We are continuing our discussion on control. Specifically we will be addressing Follow-through for the M4 and M4A1 platforms. The Reference for this discussion is TC 3-22.9 Change 1 dated January 2017.
The M4 series weapon has a variable trigger weight due to the burst trigger control group. The weight can vary as much as three to eight pounds depending upon where the sear is at in the burst cycle.
So how do we compensate for that variable trigger pull?
The answer is follow-through. Follow-through is the continued application of the shot process until after the shot has been fired. This means that the Paratrooper keeps applying the elements of the shot process until the weapon ceases movement from the recoil pulse.
A practical application of follow-through is keeping the head in the same position, firing eye (or both eyes open, in the case of the CCO and RCO), and holds the trigger back until the recoil pulse ceases, then lets off enough to allow the trigger to reset. Body position remains the same, and breathing is either steady or held, depending upon the conditions of the particular shot.
There are nine components to follow-through, they are Recoil Management, Recoil recovery, Trigger/Sear reset, Sight Picture Adjustment, Engagement Assessment, Subsequent Engagement, Supplemental Engagement, Sector Check, and Correct Malfunction. All of these will be discussed separately.
Recoil management. This includes the bolt carrier group recoiling completely and returning to battery.
Recoil recovery: This is returning to the same pre-shot position and reacquiring the sight picture. The shooter should have a good sight picture before and after the shot.
Trigger/Sear reset: Once the ejection phase of the cycle of function is complete, the weapon initiates and completes the cocking phase. As part of the cocking phase, all mechanical components associated with the trigger, disconnect, and sear are reset. Any failures in the cocking phase indicate a weapon malfunction and require the shooter to take the appropriate action. The shooter maintains trigger finger placement and releases pressure on the trigger until the sear is reset, demonstrated by a metallic click. At this point the sear is reset and the trigger pre-staged for a subsequent or supplemental engagement if needed.
Sight picture adjustment: Counteracting the physical changes in the sight picture caused by recoil impulses and returning the sight picture onto the target aiming point.
Engagement assessment: Once the sight picture returns to the original point of aim, the firer confirms the strike of the round, assesses the threat target’s state, and immediately selects one of the following courses of action:
Subsequent engagement. The threat requires additional (subsequent) rounds to achieve the desired target effect. The shooter starts the pre-shot process.
Supplemental engagement. The shooter determines the desired target effect is achieved and another threat target may require servicing. The shooter starts the pre-shot process.
Sector check. All threats have been adequately serviced to the desired effect. The shooter then checks his sector of responsibility for additional threats as the tactical situation dictates. The unit’s SOP will dictate any vocal announcements required during the post-shot sequence.
Correct Malfunction. If the firer determines during the follow-through that the weapon failed during one of the phases of the cycle of function, they make the appropriate announcement to their team and immediately execute corrective action.
So to sum up, we’ve discussed Follow-through, what it is, why it is important, what the nine components are that make up follow-through, and what the Paratrooper’s mindset should consist of during follow-through. We will continue the discussion as we address correcting malfunctions.