by Nick Depperschmidt December 28, 2017 1 Comment

Applied Ballistics has one of the most complete and accurate bullet and custom drag curve libraries in the long range shooting market. As their team cruised to a first place finish at the 2017 King of Two Miles tournament at the NRA Whittington Center, Team AB could be seen using wrist mounted devices while working up firing solutions for these extended long range (ELR) shots.

That little piece of kit was the Garmin Foretrex Ballistic Edition (GF701B). (Purchase Here) This wrist or weapon mounted device is an all-in-one, state of the art ballistic calculator and a GPS/navigation unit. It contains the entire Applied Ballistics bullet and Custom Drag Model library, more than 100 slots for gun profiles, and added memory and storage to quickly calculate firing solutions in excess of 10,000 yards.

Garmin Foretrex 701 Ballistic EditionThe GF701B is just about the perfect size for field use. Its handy size makes it well suited for use at practical/tactical rifles matches, hunting, and general outdoor recreation. But why would someone purchase the GF701B instead of a Kestrel 5700 Elite, the gold standard for gathering real time atmospherics to build multiple firing solutions in field conditions? Or perhaps why would anyone with a Kestrel add this to their loadout?

A lot of that depends on how you use the Foretrex 701, as its versatility can’t be understated. It does just about everything a 5700 Elite can do, with an added benefit of being a GPS and land navigation unit, as well as a smart device for everyday use. However, if you’re reading this on www.bisontacitical.com, you’re likely a long range rifle enthusiast so let’s talk about the Applied Ballistics side of the GF701B first.

Adding and inputting rifles can be done directly on the device without the AB profile loader, or the LiNK App. Inputting the particulars for your load and rifle is fairly simple with the four button layout. It may be a hair slower than a 5700 Elite, but with some repetition it’s no more cumbersome than the Kestrel. To upload multiple profiles, simply pop off the rear battery compartment and load rifle profiles built into AB with a microUSB cable.

The Foretrex 701 uses the full featured Applied Ballistics engine. Firing solutions are calibrated using six drop scale factors to provide the most accurate ballistic solution possible. Aerodynamic Jump, Spin Drift, Vertical Coriolis Effect, Horizontal Coriolis Effect, Max Ord, & Max Ord Range are all calculated within the system. Muzzle velocity calibration allows users to input the distance and the true drop of the bullet to determine muzzle velocity (MV) if a chronograph is not available. A MV temp table is also available to account for velocity shift with temperature fluctuations.

If scope tracking is incorrect, Sight Scale Factor has the ability to true a firing solution to the actual movement values of the scope turrets. The Foretrex 701 also includes a target speed/direction function to give a ballistic solution for shooting moving targets.

The final component of the firing solution is pulling atmospherics and wind speed/direction. Internal sensors for ballistic calculations include station pressure, latitude, and direction (compass). To grab live temperature, users would need to purchase a $30 Garmin Tempe. A worthwhile investment. Though it is recommended to clip the Tempe on a pack, away from the skin to not give false temperature readings.

The final two parameters, wind and humidity, must be inputted into the Foretrex by the user. Since the Tempe does not measure humidity, a handy way to input this would be to note the average humidity in the area for the day. I can see the comments now, “I need exact humidity!” I get it, I use exact humidity readings from my Kestrel too. However, take a quick look at what Frank Galli has to say about humidity and air density below, full article HERE. Long story short, set it and forget it.

“For 99% of our shooting we can set Humidity to 50% and ignore it. Just to confirm for those who might not understand, Higher Humidity reduces the air density. When comparing 100% vs 0% humidity, air that has 100% humidity is less dense. The difference between the two as far as the bullet is concerned is very, very small. So I just want to get humidity out of the way.”

The wind though, that is something everyone needs to have down pat for first round impacts. Anyone with a free ballistic App and decent data can get on plates with relative ease. Wind reading is what separates many shooters when the scores are tallied at the end of the day.

However, how someone manages their wind calls throughout a weekend of shooting is as different as what reticle and scope they prefer. Some people use the exact wind at their location via a device, some use full and half values at 5/10/15/20 mph increments on a printed DOPE cards, some read mirage and vegetation, or some combination of all of these methods.

If you use full and half value wind values at set wind speeds, I believe there is no determent to using the Foretrex over a Kestrel. Simply estimate the wind as normal, input it and go. Users could also purchase a WeatherFlow phone mounted weather meter to get wind speed. The downside there is that’s two devices to manage, which may be a deal breaker for some.

Garming Foretrex Target CardSo what if you’re looking to use the Foretrex 701, and only that, for PRS or NRL matches? First, I would place the Tempe on my match pack, input the average humidity for that day, and rely on the Target Card feature from there. Once the stage ranges are on the Target Card, all that’s needed is to gather wind speed/direction to complete the firing solution. Then mount it to something like a Hawk Hill rifle mounted data card holder and use it like a Sidewinder. Users could also keep it on their wrist and write DOPE on a Sidewinder system. (Purchase a Sidewinder DOPE card holder)

The additional benefit of using the Foretrex is there’s no need to worry about wet weather. With its MIL-STD-801 Compliant/IPX7 water rating it features ingress protection from water, dirt, and dust, as well as shock protection. The display is also plainly visible in both low and bright light conditions. Additionally, a timer feature allows you to set alerts to know exactly how much time you have, without having to call for time from an RO. Something that is very handy for anyone that loves to call for time.  

Outside of the practical/tactical realm, the Foretrex 701 is a powerful ELR shooting tool, and that’s exactly why Bryan Litz and his team used it during the King of Two Miles competition. One of the added benefits of the Garmin is it has more memory and a powerful processor to calculate long distance shots faster than a Kestrel. Combined with its precise GPS, it’s was built for this style of shooting.

When speaking with Doc Beech at Applied Ballistics, he noted that the Foretrex did not replace their Kestrels while at the Kind of 2 Miles event. It was used as a companion. A Kestrel provides a tool that can be taken anywhere in the world to quickly grab a wind and environmental readings at one location. However, when shooting two miles, the wind at your location is a small fraction of the overall ballistic equation. So the AB team used many devices, and leaned on the expertise of their coaches to give exact wind calls to make the first hit at two miles recorded at the competition. Their coaches have experience reading wind around the world, in varying conditions and topographies. No device can outweigh that level of experience.

One interesting item of note I learned by talking with Doc. None of the ballistic solutions were trued for the four shooter team. They simply loaded the custom drag models for the projectile, had good, hard data for velocity on each rifle, and a verified zero. They ran with that, all the way out to two miles. Something to think about the next time you’re chasing DOPE at the range.

However, the ballistic solver is just one part of this unit. Another feature that may tip the scales for anyone looking to purchase the GF701B is the GPS capabilities. This is also where I think the Foretrex would become one handy piece of kit in a long range hunter’s arsenal. The device tracks speed and direction, distance to point, has point to point navigation, saves tracks, gives grid coordinates, populates a real time crumb trail, gives elevation, vertical speed, total ascent/decent, and features TracBack, which allows you to return to a set point. The unit also supports GLONASS/Galileo global navigation systems, giving you extremely accurate location readings.

Basically, you’re not getting lost on your next hunt. Let’s say you’re 3 miles into dark timber and you take an Elk. A buddy is in the area, but not with you. The Foretrex would allow you to mark the Elk’s location so you could go back and forth humping quarters to the truck, and get some help along the way with route sharing. You could even use it to mark and measure distance to targets, something that can come in handy for match directors setting up known distance courses of fire.

The unit is also night vision compatible for night time hunts. A Foretrex with the target table and some thermal would spell big trouble for a group of hogs. It will also provide a hunting and fishing calendar, and sun and moon information.  

One drawback on the hunting side is the inability to use onX maps. Since it does not have an SD slot, onX maps cannot be loaded on to the device. So if you’re on a new piece of BLM land, skirting some private property, you may want to have your onX maps with you as well. However, if you know the area well, and are looking to mark and log locations, the Foretrex is well suited for that task.

Additional features include the ability to pair it with a smart phone for email and text alerts, and compatibility with heart rate, speed, cadence, VIRB and the aforementioned Tempe sensor. Meaning someone that is a biker, hunter, runner, and a shooter could find a lot of value in owning the GF701B. There’s also a screen for HAHO, HALO, and static line jumps/skydiving.

The physical dimensions of the Foretrex 701 are 2.9 by 1.7 by 0.9 inches, it has a 2 inch screen, and takes 2 AAA batteries. Battery life is up to 48 hours (GPS mode), Up to 1 week (UltraTrac mode), Up to 30 days (Watch mode).

That is the nitty gritty. When talking with Doc Beech at AB about how to pick one device in the AB product line, he made a good point. A Kestrel does not replace a Foretrex 701. A Foretrex does not replace a Sig Kilo 2400 ABS. They have specific roles and it’s up to the user to define the niche of their application. Do you need a GPS navigation tool? Do you need a rugged ballistic solver and aren’t overly concerned with reading wind at your location? Are you shooting ELR distances? Are you going to HALO into your next match? Make a list of all of those needs and pick the device that fills the most roles. I think a lot of people may be surprised the Foretrex 701 Ballistic Edition checks a lot of boxes.

Nick Depperschmidt
Nick Depperschmidt


1 Response

Lon
Lon

December 28, 2017

Nice blog. Does anyone ever really read the comments left by people who read the blogs?

You know how to get ahold of me. LOL

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