FX MK II Radar Wireless Bluetooth Chronograph

FX’s wireless Bluetooth chronograph uses Doppler radar to measure the speed of projectiles up to a maximum muzzle velocity of 1099 fps (335 m/s). I’m all in favour of using tools that make life easier, and from the instant I opened the FX chrono, I knew this was going to be the case. There are no instructions in the box, but the iOS or Android Apps which run the chrono also included copious, easily navigated instructions.

Getting into position

The MKII seen here has a V-bracket which can be fastened to your muzzle or buddy bottle with rubber bands. No specific alignment is required, just make sure the unit is facing towards the target. The radar then tracks the projectile travelling away from it to display the speed. You are encouraged to place the chrono as closely in line with the barrel as possible, to increase the accuracy of the recorded data (it minimises the angular displacement from the exact bore line). However, in reality, I had no problem just standing the unit under the muzzle, and I got reliable readings, although I do appreciate the mathematical merits of minimising the angle.

In use

The unit is powered by 3x AAA batteries. They go under the rear panel and you will need a Pozidrive screwdriver. There is a power button on the back as well as a battery display. Once powered up, turn your phone on and launch the app, then they will automatically detect each other and invite you to pair. It was totally straightforward and immediate without any annoying warm-up time. Once in action, you can run the app in several ways.

You can use the unit to record speeds and you can install specific profiles that are named after each of your rifles or specific projectile types. You can also enter projectile weights and chose a sensitivity mode that will most likely detect projectiles within a given energy range, so an arrow, airsoft, or low/high power air rifle. I set it on high-power air rifle and it detected sub-12 ft-lbs, .177 and .22 FAC pellets or slugs at 40 ft-lbs. It also clocked a .22 rimfire shooting a 40-grain bullet at 1050 fps. Data and graphs are produced and these can be saved or shared via the app.

You can choose preferred units for all measurements, and the FX also gives an instantaneous muzzle energy calculation if the projectile weight has been entered. The app can be silent or set to read out the velocity/energy shot after shot. Functions like magazine size are also permissible, so it even tells you that you are on your last shot.

Conclusion

Overall, the only thing you need to be aware of, is that the unit automatically powers off to save its batteries, and if you take too long to load a magazine, just make sure it’s switched back on before firing re-commences. It weighs just 133-grams and is truly pocket-sized. I cannot negatively critique this unit, which, quite frankly, makes my daily work faster and easier. A centrefire version will also be available soon, which I’m looking forward to immensely.