The Evolution of Tank Gunnery

It has been ten years since the last re­vision of the tank gunnery manual. In the coming weeks the 2025 version of the Abrams gunnery manual will be au­thenticated and formally published through the Army Publishing Director­ate (APD)1. This manual has a great number of changes from its predeces­sor, TC 3-20.31, Training and Qualifica­tion, Crew.2 Change is inevitable. Change can be good. According to C92, these are the key changes every leader should be aware of. As the Ar­mor force focuses on large-scale com­bat operations (LSCO), the evolution of tank gunnery must refocus to more complex, longer-range engagements and appropriate techniques.

The changes to the gunnery manual will be discussed over three articles. This initial article will discuss the most impactful changes at the unit level. It will be followed by the “nice to know” and “why did that change” topics. The last article will include an introduction and overview to Table Charlie: Com­plex Engagements.

The Big Changes

The largest changes in the manual are found on Tables IV, Basic, Table V, Prac­tice, and Table VI, Qualification.

Return to Platform Gunnery Manuals

As a recommendation from leaders stemming from the III Corps Lethality Report3, each platform type should have their own separate gunnery train­ing publication (gunnery manual) for simplicity. TC 3-20.31, Training and Qualification, Crew, included multiple platform training and qualification standards. From that recommendation an updated gunnery manual structure was developed similarly to that used in 1957 through 2005. The basic structure is shown in Figure 1 below. Although not all the manuals in the set, those specific to gunnery on the range are shown for simplicity.

TC 3-20.31, Training: Crew Platforms

The core publication remains TC 3-20.31 with a more refined focus on unit training plans, range require­ments, scenario development, and key planning considerations. That publication will include a series of checklists for units to build their own gunnery standard operating proce­dures (GUNSOP) and leader certifica­tion programs based on Army policy, regulatory requirements, and best practices.

There are three primary gunnery pub­lications for ABCT formation use:

  • TC 3-20.31-120, Gunnery: Heavy Tank
  • TC 3-20.31-25, Gunnery: Bradley Fighting Vehicle, 25mm
  • TC 3-20.31-404, Gunnery: Crew-Served Weapons.

The publication number from the pre­vious 2015 manual was used as the “root” number – with the addition of “-120” or “-25” to describe the caliber of the platform’s primary armament.

The “-120” and “-25” are awaiting au­thentication and official publication. TC 3-20.31-404, Gunnery: Crew-Served Machine Guns, is undergoing staffing through the remainder of FY25.

The gunnery manuals follow a common outline structure to provide a common operating picture for the user.

Chapters 1 through 6 provide an over­view of the training event, the training event definition, the purpose, method, and end state of the training, and a guide to plan, prepare, execute, and assess each event. Chapter 7 details methods to manage crews once they achieve proficiency.

Prescriptive Engagement Conditions

The “Required Performance Measures” TC 3-20.31, Training and Qualification, Crew, 20154” from the previous gun­nery manual are rescinded. This allows a far more consistent standard for all engagements in the manual. It re­moves the ability of a unit to create scenarios with minimal thresholds for training and qualification.

This manual removes the unit’s ability to create scenarios such as:

  • One defensive engagement, day and night.
  • One offensive engagement day and night.
  • One short-range machine gun engagement (<400m), day or night.
  • One long-range machine gun engagement (>600m), day or night.
  • One short-range main gun engagement (<400m), day or night.
  • One long-range main gun engagement (>1800m), day or night

Commanders may only select the se­quence of engagements, the split for day / night based on their environmen­tal conditions and select one chemical, biological, radiological, and nuclear (CBRN) engagement day and night.

This is to enable training and qualifica­tion standardization across the force, drive extended range engagements supporting large scale combat opera­tions, and eliminate scenarios that were designed toward the minimum thresholds of proficiency.

Figure 1. Gunnery Manual Structure (U.S. Army graphic)

Live Fire Accuracy Screening Test

Units must be aware of the changes with zeroing or the live fire accuracy screening test (LFAST) both Abrams and Bradley platforms. For Abrams, the procedures for conducting boresight­ing and LFAST have changed. First, the boresighting distance recommendation is moved from 1200-meters to 1600-meters, +/- 10-meters. This push­es the boresight panel out to a more tactically relevant distance. The LFAST panel range-to-target also is pushed out to 1600-meters (an increase of 100-meters). This allows crews to align their optics during boresighting proce­dures and conduct the live-fire accura­cy screening checks at a tactically rel­evant distance in keeping with the Army Calibration Policy and recom­mendations from the Armor and Engi­neer Board5. Updated standard target number 5 (ST-5) panel dimensions and construction instructions are provided as shown in figure 2.

Figure 2. ST-5 Panel Updated Dimensions (U.S. Army graphic)

The procedures for conducting the LFAST have also changed to require the gunner complete a “G” pattern on target using manual controls, ensure the appropriate ammunition type is in­dexed and loaded, lase to the target to ensure the ballistic solution is created, and release the palm switches. Once done, the gunner uses manual controls to refine the lay on target with the last movement up. When prepared-to-fire, the tank commander reports set, and the command of execution is autho­rized by C92. Using the manual firing mechanism (commonly referred to as the “master blaster”) to send the round to target.

Why is that such a big deal?

Our gunners today are relatively inex­perienced with no live-fire engage­ments under their belt. For most, LFAST is the first time a new gunner has ever fired a main gun round with purpose (not including one station unit training or OSUT). Use of manual con­trols after the ballistic solution is es­tablished and then firing with the man­ual firing mechanism eliminates flinch­ing, jerking, or anticipation movement of the gun firing. It removes gunner lay error and focuses on the fire con­trol system’s ability to calculate the ballistic solution, apply it to the main gun, and fire the round in as close to a static firing occasion as possible. The goal of the change is to eliminate crew error as much as possible from the ac­curacy screening test.

Main Gun Confirmation

Once LFAST and zeroing are complete, the unit may conduct an enhanced fire control system check for main gun en­gagements. This is not resourced with Department of the Army Pamphlet (DA Pam) 350-38, Standards in Weapons Training. To conduct these two engage­ments, each crew requires an addition­al six (6) rounds, 3 each M865A1 train­ing sabot and 3 each M1002 training Multi-Purpose Anti-Tank (MPAT) rounds. Reviewing the Army’s utiliza­tion reports over the past ten years show historically low utilization of main gun resources (below 65% of au­thorized in most units) and therefore have the ability to self-resource these engagements.

There are three primary tasks within these two engagements:

  • From a defensive firing position using a fully operational fire control system, the gunner engages one stationary tank frontal with sabot training round, followed by one moving personnel carrier with an MPAT training round.
  • Crew conducts a muzzle reference sensor Update per their technical manual (TM).
  • From a defensive firing position using a fully operational fire control system, the tank commander engages one stationary tank frontal with sabot training round, followed by one moving personnel carrier with an MPAT training round.

The LFAST coupled with these three tasks provide the crew with confidence in their fire control system, prepara­tion-to-fire procedures, maintenance procedures and processes and conduct of fire. It verifies the lead angle sensor from a stationary platform against a moving threat, amplified by using the slowest main gun round against a mov­ing target.

The crew gains additional confidence in the muzzle reference sensor update by continuing to engage from the tank commander’s position. Again, the slower round is used against the mov­ing target to ensure the lead-angle sensor and ballistic computer are func­tioning properly, as the commander’s handle and trigger.

These engagements also facilitate the platoon sergeant’s evaluation of their crew’s conduct of fire during the en­gagement while serving as the loader.

Figure 3. Engagement 43, Confirmation, gunner's power control handles, example (U.S. Army graphic)

Basic Machine Gun Engagements

Once complete, the crew continues with the defensive, basic machine gun engagements. These engagements are machine gun pure using both the co­axial machine gun and commander’s caliber .50 heavy machine gun. These engagements are designed to assist the crew with identifying any issues with their machine guns, commander’s independent thermal viewer (CITV or ITV), and also allow the platoon ser­geant to evaluate the crew’s basic con­duct of fire techniques.

Four-Target Engagements

This table introduces the crews to one offensive and one defensive four-tar­get engagements, which have not been in the live fire training strategy since the “BRAVO-THREE-SWING” or “B3S” from 2001.6

The original B3S was introduced to the Abrams fleet in 1998 where a crew fighting from a defensive position, en­gaged a stationary tank frontal and a moving tank, followed by a defilade tank frontal (15-second delay) and a set of troops (25-second delay). This engagement was a “swing” task, where it could be fired either during the day or night phase of the course of fire.

In general, not including any autho­rized defilade time, the crew must kill all 4 targets in 52 seconds to pass.

By way of comparison, placing the tar­getry from the B3S from 1998 in to­day’s threat-based scoring model un­der the same firing conditions, the crew must kill all 4 targets in under 55 seconds (again, not including defilade or break times.)

In the older scoring model, the crew also could pass the engagement if they defeated 3 of 4 of the targets (using all authorized defilade time) in a total of 42 seconds.7 Today, if a crew fails to kill any target presented within an engage­ment, they fail the engagement.

Although the targets within these en­gagements are different, without scru­tinizing the type of targets within the engagement itself, to pass the crews must defeat all targets (not just 3 of 4) presented in less than:

  • 59 seconds on the offense
  • 57 seconds from the defense.

The scoring models differ conceptually, but they don’t differ much mathemat­ically. These numbers are based on a “slowest minimum standard” calcula­tion.8 In the defense alone, the mini­mum standard appears 5-seconds slower. But the targetry within those engagements are not equal in nature. For example, Engagement 65 in the Gunnery: Heavy Tank book, provides the conditions for the four targets fired from the defense:

  • Troops, 400m (coax) – generally the same range band from the B3S.
  • Stationary PC, 1600m (MPAT) – the defilade tank is presented at 700-900 meters – 700-meters closer with a smaller target.
  • Stationary tank, 2000m (sabot) – 400-meters farther than the B3S stationary tank.
  • Moving tank, 2200m (sabot) – this is 400-meters farther than the B3S’s moving target.

The sequencing of the targets coupled with the extended range of the targets provide 5-seconds more time to kill the threats in the current scoring model.

In context to killing, the further the target, the more time to kill it is avail­able.

Minor Crew Penalties Don’t Fail You

Lastly, in older scoring models, if the crew killed all the targets and received 70-points (passing), they could have received a penalty for an error in their conduct of fire (-5 points), causing the crew to fail the engagement. Today’s scoring model does not permit conduct of fire issues (5-point penalties) from disqualifying a crew’s engagement. If the crew killed fast enough but said some things out of sequence, it will not cause the crew to fail the engage­ment.

Table V, Practice

The principles of the practice course of fire include use of ¾ scale targets at full-range and provide more challeng­ing engagements to build experience for the crew prior to the qualification course of fire, Table VI. This isn’t a change, actually… we are just high­lighting this as a critical requirement during scenario development along with the required use of battle effect simulators (BES) as part of the Army-standard target presentations.

Train Harder than the Test

That’s the most important aspect of Ta­ble V. Practice with a higher level of difficulty and the qualification course of fire will be easier.

There are other aspects of “difficulty” that are applied to Table V. The de­graded engagement conditions are more complex and difficult to master. The engagement ranges are farther – which provides more time but have a lower probability of hit (Phit).9 Other aspects of Table V require the unit to actively evaluate conduct of fire to re­duce the time it takes to announce the fire commands. The unit should prac­tice brutality evaluating the conduct of fire for each crew during simulations including Table II, Table III, Table IV, and Table V.

Enforce Speed and Violence of Action

In killing, speed and violence of action are critical for the crew’s success. For every crew that doesn’t understand conduct of fire (fire commands), valu­able time is lost. Units that do not ad­here to training conduct of fire correct­ly are the ones that habitually use “fire and adjust” for most engagements without understanding what it is actu­ally for, or that they are adding one or two additional seconds to their kill time.

The goal is for the crews to understand conduct of fire better than proper emoticon use on their phone. Say only what is necessary.

Acquisition Reports vs. Contact Reports

Crews must understand that an accu­rate acquisition report takes the place of the alert and target description ele­ments of the fire command. If done correctly, it also includes the manda­tory crew response terms for the gun­ner. TC 3-20.31-040, Direct Fire Kill Chain, and TC 3-20.31-043, Conduct of Fire, establish a clear difference be­tween a contact report and an acquisi­tion report. Contact reports are fine in­forming leaders of observed things by military description – i.e. the loader announcing

“TANK, LEFT FRONT.”

The tank commander and gunner have that contact report to react to. An ac­quisition report is provided by the gun­ner and includes a target description and range to target. This takes the place of multiple elements in the fire command AND a required crew re­sponse. For example, the gunner can provide an acquisition report of

“TANK, ONE-FOUR-HUNDRED.”

This simple acquisition report provides a sufficient target description and in­cludes the determined range to target. It is implied that the gunner identified the target description and does not need to announce “IDENTIFIED” as a crew response.

The tank commander would wait for “UP” from the loader, assess the acqui­sition report and target, and just an­nounce the command of execution…

”FIRE.”

And that speeds up the conduct of fire. That makes killing faster. That makes crews better. That increases the crew’s lethality. If units don’t train proper conduct-of-fire or reinforce that train­ing during simulations use and during every tank table, they’re placing their qualification in jeopardy.

FIRE, FIRE SABOT

In the next article, we will discuss those slight changes and nuances and explain some of the “why” and “how” behind them. We will provide back­ground information to build better context for each.

Notes

1 Army Publishing Directorate. (2025, April). APD - Army Publishing Directorate. Retrieved from ArmyPubs: https://army­pubs.army.mil/

2 TC 3-20.31, Training and Qualification, Crew. (2015). Fort Benning: Department of the Army.

3 III Armored Corps. (2019). III Armored Corps Lethality Report. Fort Hood: De­partment of the Army, III Armored Corps.

4 TC 3-20.31, Training and Qualification, Crew. (2015). Fort Benning: Department of the Army.

5 (1980). TRADOC ACN 2136, Concept Eval­uation of Battlefield Boresight Techniques and Zero Retention. Fort Knox: US Army Armor and Engineer Board.

6 FM 3-20.21, Tank Gunnery (Abrams). (2001). Fort Knox: Department of the Army.

7 FM 17-12-1-2, Tank Gunnery (Abrams) Trainer’s Guide. (1998). Fort Knox: De­partment of the Army.

8 DA Form 8265, Common Crew Score Sheet. (2015). TC 3-20.31, Training and Qualification, Crew. Fort Benning, GA: De­partment of the Army.

9 Probability of hit (Phit) for gunnery train­ing accounts for unclassified aspects of the error budget. Generally speaking, the error budget for main gun engagements inlcudes fixed biases that are mathemati­cally accounted for by the fire control sys­te, variable biases that are mostly ad­dressed by the fir control system, and random errors.