TRASOL Ballistic App From DesertTech

Recently I started playing around with the TRASOL app from DesertTech for calculating DOPE in long range shooting.  Now, if you've been reading my recent long range shooting posts, you will be familiar with the fact that I typically use data cards that are based on Density Altitude and printed out ahead of time.  While this system works well for me, I have been wanting to find an app that would allow me to make corrections on the spot if necessary, or help me to gather and test my initial DOPE when working up a new load. 

After going through the app store, looking at a number of the options available and doing some researching online, I decided that for the money, I would try out the TRASOL app from DesertTech.  It is a newer ballistic calculator and cheaper than some of the other popular options, I've read a lot of positive reviews about it from Snipers Hide and some of the local Colorado shooters that have experimented with it.  I decided to purchase the app for iTunes for use on an iPhone and iPad mini.  DesertTech later reached out to me and offered me a code to download the app on Android as well.  Most of this review will be directed to the iTunes version, as that is primarily what I will be using the app on.


TRASOL can use your location to
import atmospheric data.

Now, according to DesertTech's website: https://deserttech.com/trasol.php
"TRASOL WAS DEVELOPED for precision shooters who desire first round hit accuracy to 1500 meters and beyond. By developing new ballistic algorithms that reshape predictive flight curves to align with Doppler radar data, TRASOL provides the most accurate predictions available."

If you aren't familiar with DesertTech, they make some very interesting bullpup precision rifles.  I haven't had an opportunity to try one myself, but I have seen several in use at local precision rifle matches and at the Battle of Breakneck PRS match in Nebraska.  I would love to be able to set up one rifle in 260 Rem as a competition rifle, then switch barrels and bolts to 338 Lapua for ELR shooting, or 22-250 for shorter range practice.

Now on to the App:

After downloading TRASOL, it asks you if you want to allow the app to access your location.  This will allow your phone to import atmospheric data for the calculations.  While this is not as accurate as using a hand-held device like a Kestrel, it will still be beneficial for shooters that don't have access to the equipment to measure it for themselves.

The next option is to create or sign into a Desert Tech account.  While this is not required, it will allow you to backup your data so that you can access your DOPE from multiple devices, or recover it in the event of losing your device.  The log in that is created works on the Desert Tech website for online orders, warranty claims, etc. 

Garbage in, Garbage Out: 

I'm not the most technically savy person, but a programming saying that has become popular, is: "garbage in, garbage out."  This absolutely applies to the entry of basic information in a ballistics app.  It doesn't matter if a ballistic calculator is able to perfectly predict the flight of your bullet, if you do not enter the correct information to begin with, you will not get an accurate shooting solution. 

As we start to fill out the basic information for our rifle, load and atmospherics, you want to get accurate information.  This means as much as possible use actual measurements and not just guesses. 

To start with, choose the basic measurement formats that you want to use for the app.  Whether you are used to measuring and calculating distances in yards or meters, make sure that the app matches what you use:


Check the basic readings that the app will use.

The next step is to save a gun profile.  You can save multiple profiles for use with different guns and different loads.  In the picture below and on the left, you see how the required fields will start out red.  This shows you that it is important to fill in each field correctly.  If you are using factory ammunition, a little bit of Internet research will typically reveal the bullet weight and ballistic coefficient if you don't already know it.  As far as velocity, it is important to measure this amount yourself.  I will talk about truing your DOPE a little later, but it is important to start with an accurate number. 

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The sight height, click value and twist rate will all depend on your rifle.  It is easy to measure the sight height from the centerline of the bore to the centerline of the scope.  You can get the click value and twist rate from the manufactures of your scope and barrel respectively.  

For the zero range I would suggest sighting in for 100 yards, unless you are shooting at Extended Long Range distances.  100 yard ranges are much more common, making it easier to check your zero.  There is also less impact on your point of impact at 100 yards due to changes in altitude or weather than with a longer range zero.

Once you enter the basic information for your rifle and load combination, make sure you save it for later use.  You can save multiple loads or firearms if you choose.  The load listed above is my current competition load for the 260 Remington.  I also used TRASOL to calculate the DOPE for a load with Hornady's ELD-X bullet for hunting.  I used the data on an Antelope hunt this year, I successfully filled the doe tag, but ultimately only ended up taking a 100 yard shot, negating the need for detailed drop data. 

Taking The Shot:

With your load saved, it is time to enter the specific information for the shot.  The first thing is to enter the atmospheric data for your current location and weather.  One thing I really like about the TRASOL app is that it is designed to work with Density Altitude.  I recently wrote a post that explains What is Density Altitude?  I like to use Density Altitude when possible because it takes all of the other weather and altitude variables and creates a single equivalent number to make it easy to calculate.  If you don't have the ability to calculate Density Altitude on your own, the app can use your phone to calculate it for your area.

In the ballistics tab below you can see that it also allows you to enter the range to target, wind information, target movement information, slope, Coriolis, cant and Cold Bore shift.  The more information that you can provide, the more accurate the calculations are.  At the top of the screen you can see the quick display for the range that you selected.  It shows that for 675 yards, my adjustment would be 13.5 MOA up and a 10 MPH wind at 90 degrees would require 2.8 MOA of adjustment. 

The information bar at the top of the screen is convenient if you are about to make a single shot at a specific distance, or if you are going to make multiple shots at a single distance, but what if you want to engage targets at multiple distances?  If you click "Table" at the top right of the screen you will get a drop chart as pictured below: 

I find the ballistic table much more convenient for the type of shooting that I tend to do.  If you are checking your DOPE at multiple distances or shooting a match stage that requires engagement at multiple distances, it is easy to generate the table, then add the correct adjustments to your wrist coach, notepad, or whatever you are using.  The total distance and intervals between yardages are based on what you told the app to calculate in the bottom of the settings page shown towards the top.  This allows you to calculate as precisely and or as far as necessary.  For the typical local matches that I shoot, I rarely need to go more that about 1200 yards.  If you are taking your 338 Lapua Magnum out to ELR distances, the app will still work just as well for you.

Sighting In For Hunting

The photos above show the calculations I got from entering the information that I was already using for my match load.  I was previously using DOPE cards based on Density Altitude and I was pleased that the drops calculated by TRASOL seemed to match up with the cards that I was already using.  I decided to that to really test it, I needed to develop a new load.

I drew my first Antelope tag for 2016.  It was just for a doe, but I figured that my match rifle in 260 Remington was a good match for possible long range shots in the prairie.  I picked up some of the new Hornady ELD-X bullets to try out in my rifle.  I shot at a local 100 range to get a basic zero established and to get some velocity readings. 
The next weekend I went out to another range that had steel targets out to 1000 yards.  I wasn't planning on shooting at an Antelope at those distances, but I still wanted to see how the bullets and app would perform at long distances.  Unfortunately, when I got to the range, I found out that some of the steel was no longer up and the longest shot would be about 575 yards.  This was plenty for hunting purposes, but means I wasn't able to test the app the way I wanted to.

I started off by entering the information I had for my load and using a Kestrel to get my Density Altitude for the location that I was shooting.  I then confirmed my zero at 100 yards and started reaching out to the longer steel targets.

I had to make some small adjustments (see Truing your DOPE below:), but was quickly hitting prairie dog targets out to the full 575 yard length.  When I confirmed my DOPE with my previous load I had to take copious notes, then return home and use a web-based ballistic calculator to true my data with what I saw in the field.  With TRASOL I was able to make adjustments as I went and then save the end product, ready to use in the field.

HUD Display

One of the more unique features is the Heads Up Display (HUD) that the TRASOL app offers.  I haven't seen this on any of the other apps that I have tried out.  It can take the location and atmospheric data that your phone provides and display an overlay on an image from your phone's camera.  This allows you to actually point your phone at the target and get a firing solution based on the direction that your phone is pointed. This includes the angle of fire and azimuth for the direction that you are shooting.

Now, your phone can't calculate wind and distances on it's own, but the app uses a pretty interesting system of sliding to adjust the wind angle, wind speed and distance.  It can also calculate angles based on the orientation of the phone.  Once you've entered the wind and distance info, the top right corner (see above) displays your elevation adjustment, wind hold and lead.  There is also a provision for recording photos and video of the display.

While I don't see a lot of use for this in a competition setting, I could see setting this up and using it while working up a load.  You could even attach it to a spotting scope with the appropriate adapter and record the DOPE that you use, and the resulting shots, whether they hit or miss.  It could be a way to have a visual data book.

Truing Your DOPE

So what exactly is truing your DOPE?  For a number of reasons, the information that you gather and enter in the ballistic calculator may not be exactly correct.  Remember the garbage in, garbage out above?  The ballistic coefficient that is provided by a lot of manufacturers can be off, typically over-estimated to look better.  The velocity that you collected could be off, especially if you use the manufacturer's number from factory ammo.  It can also be off depending on the quality of the chronograph you use, or the distance in front of the muzzle. 

The way to overcome those small errors is to take the initial information that you gathered and shoot it at multiple distances, preferably all the way to the longest distance that you want to shoot to.  You then record the actual amount of adjustment that you needed compared to what the app says you should have used.  You can then start adjusting the ballistic coefficient or velocity in small increments until you get a ballistic table that matches the actual adjustments that you made.

When I sighted in my new hunting load, TRASOL was very close to where I needed to be, but even with a very high quality ballistic app, the time spending truing the data is never misspent. 

Not All Perfect

So what would I change about the app?  Although I was please overall with the performance and format of TRASOL, there were a few bugs or things that I would like to see done differently.

The biggest issue I had early on was the app crashing as I was trying to input my data for the first time.  I would enter info for my equipment, saving after every couple fields that I entered.  Almost every time that I saved, the app would crash.  I don't know if it was specific to saving after only changing a field or two, but this was with an iPhone 7+ that was only a week old at the time.  I did notice that after I got the initial info saved and added new loads and rifles I haven't seen the app crash since.  I don't know if the bugs were fixed in an update, or if it was something to do with saving the initial data.  Either way it was very frustrating at first.

Next, I would like to see a provision for truing DOPE.  As I talked about above, even though the ballistic calculator seems to be very accurate, depending on the quality of input information, there is almost always a need to tweak the data.  Some apps out there have the ability to directly input the tested, correct drop for specific ranges, then it calculates the correct drop.  While I was able to do it by changing BC or velocity to get the right numbers, it would be nice to have a truing feature.

I am surprised there is no option to enter specific atmospheric data.  Now, don't get me wrong, as mentioned above I really like using Density Altitude.  I think that is the best method overall, but I know that there are still a lot of shooters that don't have the ability to measure DA.  It would be nice to see an option to enter actual barometric pressure, altitude, temp, humidity, etc to calculate drop.

I may be the only person that would use this feature, but I would like to see the ability to use a mix and match of MIL and MOA for elevation and windage.  I have an older scope that has a MIL reticle and MOA adjustments.  On my DOPE cards I calculated elevation as MOA to dial, but calculate windage based on MIL so that I can hold off using the reticle.  I'm sure there isn't a huge market for it, but it would be nice to be able to use that, at least until I update my scope.  I wrote a more detailed post about it: Shooting with MOA Turrets and a MIL Reticle.