For those unfamiliar with a ballistic chronograph, it’s basically a device for measuring the velocity of your projectile. Modern chronographs allow you to input and extrapolate a lot more information than just the speed, but the core purpose is still measuring velocity.
Buying a chronograph is a natural progression for a reloader as the detailed data gathered is crucial to your journey down the rabbit hole of consistent and repeatable accuracy. Manipulating handloaded ammunition to achieve accuracy and repeatability is an art form and very addictive. The chronograph will allow the canny reloader to explore areas of increased accuracy and manipulate the load characteristics to hopefully achieve the best rifle/load combination. It also allows a detailed exploration of your trajectory. It’s not essential to most hunters but becomes essential when working on detailed ballistic information such as is required for long-range shooting. I still recommend every hunter should have a solid understanding of their own rifle’s velocity and trajectory; if that means befriending someone with a chronograph, so be it!
The chronograph has come a long way with many innovations and technological advances coming online over the last couple of decades. The inclusion of Doppler radar or the use of magnets to measure velocity has broadened the operating systems available. By far, the most cost-effective way to satisfy your inner ballistics nerd is still a chronograph like Caldwell’s G2 which uses the traditional method of measuring the time it takes for the projectile to pass under its front and rear sensors – known as the optical method.
Let’s take a closer look at the Caldwell G2 Chronograph.
Compact Carry Case
The G2 comes in a very nifty carry case which accommodates the whole unit including the recharging cable and tripod. The compartments are snug and well designed – a definite bonus when storing and transporting your G2.
Most of you familiar with optical chronographs will notice the G2 looks different; this is because they’ve basically flipped the unit over so it’s the opposite way to traditional systems. On most optical chronographs, the sensors read from the bottom looking up whereas the G2 reads from the top looking down toward the LED lights. This solved a common fault with the old system because when light conditions were too bright, the sensors struggled (looking up towards the sky) to pick up the projectile; the sensors were basically blinded by the light – this led to a lot of frustrating error messages. By inverting the system and adding LED lights along the bottom, the G2’s ability to pick up the projectile is increased.
Internal Lithium Battery
A great feature of the G2 is the internal lithium ion battery. This takes away the need to carry spare batteries or require a power source at the range; simply charge your battery in the evening. On the phone app, there’s a battery icon showing the remaining life of the chronograph’s battery. The longest I had the chronograph turned on for was 3hrs and a total of 100 shots; on the app, this showed a 40% reduction in the battery – using that information conservatively, I’d assess the total battery lifespan at around 5-6 hours.
The App and Bluetooth Connection
A definite improvement on the old system is the introduction of a wireless connection between the phone app and the unit. Traditionally, a wire connecting the unit to a command box next to you allowed control of the app/data. Having fewer wires makes for a simpler, tidier set-up and operation.
The Caldwell application can be downloaded for Android or IOS (Apple products). The app, once opened, immediately tries to Bluetooth connect with the chronograph; push ‘STOP SCAN’ if you want to just use the app/data offline. The app will connect to the chronograph very quickly if it’s in range, and it’s a simple process to enter load/ammunition data, shoot a string, save the string, rename, then continue. The data is all saved on the app on your phone and by pushing ‘share’ you can send via email or SMS (text message). The app allows the logging of temperature, barometric pressure, ballistic coefficient and bullet weight as well as any additional notes. You can switch between metres per second (metric) and feet per second (imperial).
The app is designed to capture velocity with some standard data for ballistics; if you want to do a deep dive into your data, a dedicated ballistic app like Strelok or similar will be needed.
The G2 app is simple to use, and it’s very easy to send and use the data. There are more detailed systems out there but with the addition of a dedicated ballistic app, you’ll have all the information you need.
Functionality and Usability
Setting up is dead simple, but once attached to the tripod and you’re ready to position the G2, it’s important to take the time to properly align your unit with your target. The picture above shows the sweet spot for getting 98% of readings with the unit; shooting outside this will induce some error readings, so taking the time to align properly is key.
The tripod provided is the main weakness I’ve identified with the chronograph; it’s cheaply made and not as stable as you’d want, especially if it’s windy. It works fine, but there are much better tripods on the market.
Once aligned, turn on both your phone application and the G2 unit – the connection occurs promptly. From here, it’s a very simple system of shoot, save, repeat with an occasional realignment if switching targets. Velocities can be read by glancing down at your phone or by checking the screen on the main unit facing you.
Calibres used for testing were .17hmr, .204, 6.5×55 and .308. I was lucky to have access to this range of calibres as it’s important to test if the unit will pick up the smaller faster calibres as well as your standard velocity centrefires. The unit worked extremely well; if the projectile goes through the correctly aligned area, you’ll get a reading.
The internal rechargeable battery and compact carry case make the G2 easy to transport and set up. It’s user-friendly and a great chronograph to suit most shooters. High volume shooters and reloaders will probably still favour Doppler radar, which is hard to beat for ease of use; however, there’s a very large price increase.
The application is simple to use, connects quickly to the main unit and allows a good amount of information to be gathered. Coupled with a dedicated ballistic application, you can deep dive your data to your heart’s content. When firing through the sweet spot, the readings were about 98% consistent whether the projectile was the .17hmr or the .308; if not aligned, you’ll receive some ‘error readings’, but that’s down to operator fault.
The tripod provided adds to the compact and user-friendly nature of the G2. However, it’s not as stable and easy to use as an off-the-shelf tripod – for that reason, I substituted the Manfrotto BeFree tripod. If you intend to use the G2 for a high volume of shooting, I recommend replacing the tripod.
In conclusion, as far as optical/traditional chronographs go, this is the best I’ve used.
Next issue, we review Caldwell’s Series One entry-level ballistic chronograph.