Horus ATragMX software considers atmospheric conditions, gun data, ammunition, range, speed and muzzle velocity to calculate precise aiming solutions with "come-up" results – and even accounts for Coriolis and spin drift effects. ATragMX, loaded on a handheld computer made by TDS Recon, is easy to use and lightning-fast. The Recon meets the rigorous MIL-STD-810F military standard for drops, vibration, humidity, altitude and extreme temperatures.
- Open the [Range Card]({{ site.baseurl }}/wiki/feature/rangecard.html) and check the ammunition: bullet diameter, bullet weight, rifle twist, muzzle velocity at 15°C, zeroed distance and bore height.
- Update the `Target` column and `Done`. Requirement: [wind arrow]({{ site.baseurl }}/wiki/feature/weather.html), [Protractor]({{ site.baseurl }}/wiki/feature/advanced-ballistics#22-protractor.html), [Map Tools]({{ site.baseurl }}/wiki/feature/maptools.html). For advanced tools: [ACE3 Equipment]({{ site.baseurl }}/wiki/feature.html).
-`Latitude`: *[ACE3 Github]({{ site.ace.githubUrl }}/blob/master/addons/common/functions/fnc_getMapData.sqf) or Eden Editor's Extended Debug Console: Watch:*`ace_common_maplatitude`.
-`Dir of Fire (deg from N)`: *The value is therefore given as the direction of the barrel axis from true north.***[Horus manual p.14]**
-`Wind speed (m/s)`: *Two wind speed values (low and high) may be entered on the target screen,[...] Lead/Wind2 button on the screen.***[Horus manual p.32]**
- *Wind takes into account geographic location, season, time of day, obstacles, altitude and surface roughness: [Wind Profile](https://wind-data.ch/tools/profile.php?lng=en).*
-`Wind Direction (clock)`: *Wind Direction is expressed in clock points.[...], wind is always described in terms of where it is coming from.***[Horus manual p.16]**
-`Inclination Angle`: *The degrees field is marked with a “d” and the cosine field with a “c”.***[Horus manual p.33]**
-`Target Range (meters)`: *Parameter Limits minimum and maximum values: 25 - 3700 meters.***[Horus manual p.17]**
- Apply vertical (Page Up and Down keys as default) and horizontal (Left Ctrl + Page Up and Down keys as default) elevations to the [scope]({{ site.baseurl }}/wiki/feature/scopes.html).
- Hold Breath (Left Shift as default) and Fire (Prim. Mouse. Btn. as default).
> This process is called “Truing Drop”, or simply “Truing”. It involves taking 2 or 3 real flight data points (finding bullet drop at 2 or 3 places along its flight) and feeding it into the calculation parameters. **[Horus manual p.23]**
> The Truing Drop function is opened from ATrag’s main screen by selecting “Options” [...], then selecting “Truing Drop” from the menu that appears. **[Horus manual p.23]**
> With C1, you can also insert the new BC into the C1 table (with the target range value), or you can replace the C1 table with the following values:
> 1. first entry: Zero Range, original C1.
> 2. second entry: range at 75% of distance between transonic start and subsonic start, with original C1.
> 3. third entry: range 200 (y/m) beyond subsonic start, with new calculated C1. **[Horus manual p.24]**
- Basic example with ammunition 7.62x51mm G7 ballistic coefficient.
- Open the AtragMx and the `Atmsphr` column, select `Default` and `Done`.
-`Open Gun` a custom profile in the `GunList`.
- *More information about custom profile: [Example with `Add New Gun` in `GunList`](#35-example-with-add-new-gun-in-gunlist).*
- Check `Elev` = 0 with `ZR` = `TR`*(if not, open `Gun` column and `Done`)*.
- Open the `Truing Drop` in the `Options` menu.
- Add the actual `Target Range` in the `SUPER` column and `Calc`.
- Add the same `Target Range` in the `SUB` column and `Calc`.
- Apply the actual scope elevation in the `Drop` field and `Calc`.
-`Accept` the new `C1`, `Gun` column and `Elev` are updated.
- *C1 Ballistic Coefficient vs. Distance Interpolation Table (`Options` / `Drag Coef Table`) will be updated.*
- Optionally, `Save Gun` and `Done` in the `GunList`.
- The `Default zero distance` can be overwritten with the [Scopes Options]({{ site.baseurl }}/wiki/feature/scopes.html), the [Scopes Framework]({{ site.baseurl }}/wiki/framework/scopes-framework.html) or the [CBA Settings System](https://github.com/CBATeam/CBA_A3/wiki/CBA-Settings-System).
- Open the [Range Card]({{ site.baseurl }}/wiki/feature/rangecard.html) and check the ammunition: **bullet Class Name**, bullet diameter, bullet weight, rifle twist, muzzle velocities, zeroed distance and bore height.
- Open the AtragMx and the `Atmsphr` column, select `Default` and `Done`.
- *The AtragMx accepts only **G1 ballistic coefficient**.*
- *G7 ballistic coefficient can be converted, for example, with the online [JBM Ballistics Calculators](http://www.jbmballistics.com/cgi-bin/jbmgf-5.1.cgi)*.
> Note: The ballistic coefficient can be calculated by using the [360 Degree Training Course mission](#5-resources) as a chronograph at different distances and [JBM Ballistics Calculators](http://www.jbmballistics.com/cgi-bin/jbmbcv-5.1.cgi) for example, an another ballistic software at your own convenience, or the [AtragMx Truing Tool](#33-example-with-truing-tool).
### 3.6 Connecting AtragMx with Vector 21 and DAGR
- Requirement: [Vector]({{ site.baseurl }}/wiki/framework/vector.html) and [DAGR]({{ site.baseurl }}/wiki/framework/dagr.html).
- Open the self interaction menu <kbd>Ctrl</kbd> + <kbd>⊞ Win</kbd>.
- Select `Equipment`.
- Select `Configure DAGR` and `CONNECT TO` (DOWN and HELP/SEL) `Vector 21`(HELP/SEL).
- Equip and use the Vector (B key as default).
- Check target's [slope distance and azimuth]({{ site.baseurl }}/wiki/feature/vector#23-slope-distance-and-azimuth.html) (hold both R and Tab keys as default).
- Open the [AtragMx properly configured before]({{ site.baseurl }}/wiki/feature/atragmx#32-example-with-m14-and-default-762mm-20rnd-mag.html) according to current rifle and ammunition.
- Open the `Target` column: `Dir of Fire (deg from N)`, `Inclination Angle` and `Target Range (meters)` updated with Vector's values.
### 3.8 Example with AtragMx and default ballistic (M14, 7.62mm 20Rnd Mag)
> Note: ACE3 has two external ballistics, the vanilla default ballistic (enabled as default) and the [Advanced Ballistics]({{ site.baseurl }}/wiki/feature/advanced-ballistics.html) (must be enabled). The ACE3 default ballistic doesn't take atmospheric conditions (except wind), powder temperature, rifle twist and Earth effects into account. The AtragMx will need for `Gun` column: `Bore`, `C1 Coefficient`, `Muzzle Velocity` and `Zero Range`. With `Target` column, `Latitude` and `Dir of Fire` are useless. `Atmsphr` column must not be updated.
**Start of the mission:**
- Open the [Range Card]({{ site.baseurl }}/wiki/feature/rangecard.html) and check the ammunition: **bullet Class Name**, muzzle velocity, zeroed distance and bore height.
- Open the AtragMx and the `Atmsphr` column, select `Default` and `Done`.
- Select `E` (English unit) at the top right.
- Open the `Gun` column, check and update the `Bore (inches)` and `Done`.
- Select `M` (Metric unit) at the top right.
- Open the `Gun` column, check and update the `Muzzle Velocity (m/s)`, the `Zero Range (meters)` and `Done`.
-`C1 coefficient` of the bullet = `airFriction x -1000`.
-`airFriction` can be found with the Eden Editor `Config Viewer`:
> configfile >> "CfgAmmo" >> "**bullet Class Name**" >> "airFriction"
- *AtragMx is configured with `C1 coefficient` according to vanilla weapons and its ammunitions in `GunList`.*
- *Spin drift and Earth effects not taken into account, `Options` / `Show Coriolis` can be disabled.*
- Check `Elev` = 0 with `ZR` = `TR`*(if not, open `Gun` column and `Done`)*.
- Optionally, `Save Gun` and `Done` in the `GunList`.
**In position:**
- **Do not update the `Atmsphr` column.** Default ballistic doesn't take into account temperature, pressure and humidity.
- Update the `Target` column and `Done`. Requirement: [wind arrow]({{ site.baseurl }}/wiki/feature/weather.html), [Protractor]({{ site.baseurl }}/wiki/feature/advanced-ballistics#22-protractor.html), [Map Tools]({{ site.baseurl }}/wiki/feature/maptools.html). For advanced tools: [ACE3 Equipment]({{ site.baseurl }}/wiki/feature.html).
-`Wind speed (m/s)`: *Two wind speed values (low and high) may be entered on the target screen,[...] Lead/Wind2 button on the screen.***[Horus manual p.32]**
- *Wind takes into account geographic location, season, time of day and obstacles.*
-`Wind Direction (clock)`: *Wind Direction is expressed in clock points.[...], wind is always described in terms of where it is coming from.***[Horus manual p.16]**
-`Inclination Angle`: *The degrees field is marked with a “d” and the cosine field with a “c”.***[Horus manual p.33]**
-`Target Range (meters)`: *Parameter Limits minimum and maximum values: 25 - 3700 meters.***[Horus manual p.17]**
- Apply vertical (Page Up and Down keys as default) and horizontal (Left Ctrl + Page Up and Down keys as default) elevations to the [scope]({{ site.baseurl }}/wiki/feature/scopes.html).
- Hold Breath (Left Shift as default) and Fire (Prim. Mouse. Btn. as default).
