As The OWLs Hoot: The Future One-Way Tracer

Last year, we reported on the Army’s effort to develop a non-pyrotechnic tracer round which would provide “One-Way Luminescence” (OWL) revealing the shotline to the shooter only, and not in a 360 degree arc around the gun. The benefits of this kind of tracer go beyond low visibility, however. A non-pyrotechnic tracer would be low profile, able to be stuck to the back of the standard ball bullet, improving the effectiveness of the tracer rounds that actually hit the target. It would be cheaper, and would wear out the weapon’s barrel less quickly. Finally, the trajectory of OWL non-pyrotechnic tracers would more closely match that of the standard ball ammunition, improving hit probability, and could potentially allow every round fired to be a tracer.

At the recent NDIA Small Arms Forum, three presentations related to the new tracer effort were given, one detailing the possible mechanisms for non-pyrotechnic tracers, one covering simulations of the tracer’s performance in different conditions, and one on a propellant analysis done to aid the program.


2015-06-25 01_58_13-www.dtic.mil_ndia_2015smallarms_17339_Horch.pdf

An overview of the potential benefits of the new OWL non-pyrotechnic tracer concept, illustrating the vast improvement in tracer signature.


One-way non-pyrotechnic tracers are a part of the current effort to improve small arms in a time of shrinking budgets. If the technology is perfected, US and allied soldiers could gain a major advantage in hit probability and stealth over adversaries using pyrotechnic tracer technology.

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at


  • Jeff Smith

    This sums up my thoughts.

  • TheNotoriousIUD

    They should just put rails on the bullets and mount flashlights.

    • Jack

      Skip the rails and go m-lok/key mod

    • The Brigadier


  • I have seen claims that the jacketed bases of OTM projectiles can reflect enough light from IR laser illuminators to be seen through NVG.

    • Giolli Joker

      But then the IR beam is visible through enemies’ NVGs as well…

      • True, but the US military certainly issues a lot of IR lasers as it now stands.

        • Giolli Joker

          May it be because they’re mostly facing insurgents and not properly equipped regular armies?

        • The Brigadier

          yes indeed.

  • Devil_Doc

    I was a corpsman, so this might be a stupid question. But… What happens if you’re trying to mark a target for another squad? What about identifying a target for aircraft?

    • Rock or Something

      I’m guessing if you are marking for someone else with the new tracer, they will still see it from a certain angle (ie a squad leader directing fire for his troops). If a squad is some distance away, even with conventional tracers you aren’t going to rely on that alone to spot the enemy, you will communicate that information to them. As for Aircraft, unless they are a WWI era bi-plane, I doubt pilots base their targeting runs purely on the direction of the tracers.

    • PEQs?

      • CommonSense23

        Yeah, you either are going to use your laser for fellow ground forces are a dedicated laser for air.

    • The Brigadier

      Use lasers and see them with appropriate optics. I am against painting targets with visible lasers because that also gives your target valid information to get out of Dodge.

  • Bullphrog855

    I wonder if this could stabilize in 1:9 twist barrels. IIRC the current tracer round is the reason the US uses 1:7 twist, which sacrifice accuracy for the 855/855a1 rounds

    • M855 is inaccurate due to the design, not due to twist rate.

      Unless the round is spun so fast that it breaks apart the accuracy difference between optimal twist rate, and too fast of a twist rate is small.

      • Bullphrog855

        According to American Rifleman which did a pretty good article on the 855a1. Out of a 1:7 twist you get 1.6 MOA, out of 1:9 twist you get ~.8 MOA at 100 yards, this is with 855a1. They also claim it doubles the 855 MOA as well. I feel like that’s a bit more than ‘small’, specially if you’re fighting in places like A-stan.

        You also gain longer barrel life out of a lower twist rate like the 1:9 for what it maters.

        Either way, I’m not asking about what happens to the 855, I’m curious if OWL can match the consistency of 855/855a1 out of 1:9 twist barrels. Since M856 can’t.

        • M855A1 doesn’t have the issues that M855 has due to the manufacturing process for M855A1.

          And I’ve gotten sub-MOA with a 1:7″ barrel using 55gr match ammo, something the internet has told me isn’t possible as 1:12″ is the best twist rate for 55gr ammo.

          I looked at the article it doesn’t sound very scientific (no details of how it was conducted). For all we know that the 1:7″ upper that they used simply wasn’t very accurate in the first place.

          • Exactly. The biggest issue with using. 1:7″ twist with ball ammo like the M855, M855A1, and M193 is that the barrel wears out faster when your “overspinning” the round.

            OTIH, I’ve seen 1:9″ barrels that lost accuracy with M855 (and I presume the same would happen with M855A1 or any SS109 ball) in below freezing temperatures – the same problem the Army found with the original 1:14″ twist and the 55gr bullet, back when they first tested the AR15.

            And 1:9″ doesn’t work as well with other, long for caliber, rounds in the DoD inventory.

            Big Army would rather lose barrel life than lose accuracy because the temperature dropped or they were using something like Mk262.

  • S O

    There are disadvantages indeed:
    (1) Historically some tracers were MEANT to be visible from the front, to scare. 50cal AP-I for bomber defence during WW2, for example.
    (2) Communication by tracers. Laser target designation doesn’t even come close to doing the same. A battlefield seems to be empty, the ability to see what others are shooting at provides valuable information.
    (3) Non-pyrotechnic tracers won’t provide a reliable self-destruction approach for HE shells (20 mm etc.)

    Furthermore, dark ignition or delayed tracers that light up only after about 30 metres or more have been around for more than 70 years. They don’t give away the infantryman’s location precisely.

    • Target marking shouldn’t be much of a problem, at least within the squad or fire team – generally speaking, the people you’re trying to show where to shoot will also be behind the bullets, and should be able to see the trace.

      Now, it will adversely affect your ability to spook an attacking aircraft into flinching, since the pilot won’t see the tracer at all. Since that’s *really* the point of small arms fire on attacking aircraft, that could be an issue. But one which will come up far less often than the downsides of more conventional tracers.

  • The Brigadier

    That should help eliminate the eternal question, “Did anyone see where my shot went?”