Marine Corps: Optics vs. Iron Sights

The official position from the U.S. Marine Corps and the use of iron sights. There is no data indicating that starting new shooters with iron sights provides any special benefit.

Chief Warrant Officer 2 Billy Shinault, Officer-in-charge of Chosin Rifle Range at Marine Corps Recruit Depot Parris Island, along with Warrant Officer Bobby Yarbrough, MCRD Parris Island CommStrat, explain the advantages of training recruits to start shooting with the Rifle Combat Optic instead of using iron sights.

In 2016, the Marine Corps started phasing out the legacy M16 iron sights. The iron sights were replaced by the micro backup iron sights, which are modular attachments that can be affixed to a rifle's rail mount and flipped up for use.

Each year, Marine Corps gunners and range officers meet to discuss to the Marine Corps Marksmanship Program and what changes they can make to improve the program and increase the lethality of the individual Marine. The operational environment of the modern battlefield and the irregular warfare of Afghanistan and Iraq influenced the Marine Corps' decision to adopt technology to improve the combat effectiveness of the Marine Corps.

The fundamentals of marksmanship haven't changed. Recruits still complete "snapping in" on a barrel just as the Marines from WWII, Vietnam, and Korea. The difference is now by injecting technology, we are drastically advancing the marksmanship learning curve to build greater lethality. Technology allows the Marine Corps to build more critically thinking Marines who can take a greater role in their own marksmanship development.

In 2018, Secretary James Mattis published his vision for the National Defense Strategy which included increasing the lethality of the armed forces. He said it best: "We cannot expect success fighting tomorrow's conflict with yesterday's weapons or equipment."

The fundamentals of marksmanship do not change from the RCO to iron sights. Marines at recruit training are taught on the same weapon system they would carry into combat if they deployed today. If Marines do find themselves in a situation in their career in which the optic is damaged, the Marine would use the same fundamentals with a back up sight to overcome the adversity.

There is no data (NONE!) indicating that starting new shooters with iron sights provides any special benefit nor that starting with optics is detrimental.

This mythology persists only because so many people (most of whom simply don’t know any better) continue to parrot it. I’ll be happy to change my position if anyone can provide solid evidence to the contrary but such evidence continues to be lacking. That this myth persists among current and former military is yet another example of how broken military marksmanship training is and how misinformed many military personnel are on the subject.

Despite all the griping, neither the Marine Corps nor the Army has any evidence or data to suggest that starting recruits with optics creates a disadvantage or that starting with iron sights is uniquely beneficial.

Let me say that again: There is no data or evidence to suggest that starting recruits with iron sights provide any benefit in marksmanship training. The USMC and Army have no evidence for this, and I’m confident nobody else does. I’ll welcome any real data or evidence to the contrary but most people claiming “evidence” on this are just regurgitating conjecture (i.e., made-up bullshit) and their personal feelings.

My take: In an institutional setting, once the decision has been made as to what equipment will be general issue and primary, then that needs to receive initial and primary attention in training. Most personnel are not shooters and it's a disservice to dilute their already-limited training time with secondary concerns that they won't even qualify with. For the actual marksmen, cross-training can offer benefits but that's far removed from trying to get recruits to pass qualification. Most personnel are better off focusing on whatever they're issued, not secondary concerns.

Marine Corps Marksmanship Leaders at Trijicon

Years ago, I attended a training seminar hosted by Trijicon on the use of their Advanced Combat Optical Gunsight (ACOG) issued as the M150 RCO (Trijicon TA31RCO-A4CP 4x32 BAC Rifle Combat Optic) as the primary sight for all Marines, not just Designated Marksmen. Marines in the class told us one primary reason the Corps was pushing the M150 down to everyone was observation benefits. In urban environments, many unknown contacts were noncombatants but all needed to be identified to weed out hostiles. For many squads, the designated marksman was the only person with an optical sight and squads were becoming overly dependent on one person to identify potential threats for an entire squad. In addition to the TA31 dual-illuminated chevron, the Marine's ACOG features a horizontal mil scale to give correction for observation and fires.

Yes, you sometimes hear the self-appointed “old guard” griping about new recruits and current Marines qualifying with optics. The marksmanship skills used are the same.

The USMC uses well-defined targets on Table 1 of their simplified National Match known distance qualification that all Marines shoot. A skilled shooter shouldn't have much difference in score between iron or optical sights on that course, particularly given how enormous those targets are. The ACOG shows its own at unknown ranges against varied targets against a natural or irregular background, hence the USMC’s interest.

By the 1830s there were formal, written accounts of optics. The Improved American Rifle was written in the 1840s and discussed their manufacture. A number of designs came out prior to the Civil War. Despite being a delicate technology still in its infancy, optics were used by both sides.

While optical sights found regular military use by the mid-1800s, they were limited to precision use for sniping only. For over a century, optical sights remained too delicate for common issue. It wasn't until the 1970s that optical devices became common issue on standard service rifles.

The Austrian F88 (Steyr AUG “Austeyr”) and and F89 (FN Minimi), Canadian C7 (Colt Canada) with Elcan, and the British SUSAT and other optics on the SA80 series were among the first to be general military issue.

Other countries quickly followed suit. We did as well. If anything, the United States has been very slow to adopt optics as primary sights. Allied nations were about two decades ahead of the U.S. on this even though we’ve had good options to use.

Starting in 1981 with an Occluded Eye Gunsight, Trijicon makes a variety of optics for military, law enforcement, and individual shooters. The company introduced their TA01 4x32 Advanced Combat Optical Gunsight (ACOG) in 1987 and the sight was included in the U.S. Army Advanced Combat Rifle program. While the ACR program ultimately did not replace the M16 series, the ACOG found its way into general issue. The ACOG was first used in action during Operation Just Cause in Panama in 1989 and then during Desert Storm. It has remained an issue optic ever since and is offered with a host of features.

The question is not, “Why are we now using optics instead of iron sights?” The real question is, “Why did it take so long to make optics general issue?”