Ballistic Solvers: What You Need to Know Without the Fluff

 

Ballistic Solvers: What You Need to Know Without the Fluff

What’s a ballistic solver? It’s simply a tool (usually an app or other handheld device) into which you enter details about your rifle, ammo, and environment. The solver calculates a ballistic solution based on those inputs: the exact elevation and wind adjustments you need to dial or hold on your optic to hit your target at a given distance.

I'm not here to tell you which solver to use. In fact, there are so many that I haven’t tried, I couldn’t give you a well-rounded/educated opinion on which one is best.

That said, I’ve used and enjoyed the following solvers:

1. Applied Ballistics Quantum
2. Revic Ops
3. StrelokPro
4. Hornady 4DOF

Regardless of which solver/app you choose, the key to using them successfully is to avoid overcomplicating things. I’m no ballistician, I’m no wind whisperer, and I’m no genius! But I do know how to make first round impacts! That’s what’s important, and that’s what I want to share with you.

Over the past decade or so, shooting long range has been demystified. At the end of the day, it’s math. That math, which used to be calculated manually, can now be done rapidly by a ballistic solver. So really, to shoot long range well, all you need is an understanding of the inputs the ballistic solver calls for. Then, trust the output. Sure, there’s skill behind the rifle too, but the solver does the math.

Let's make this simple. I’ll give you the solver inputs needed to get first round impacts downrange. Period! No fluff!

We’ll break this down into three parts. Rifle, Ammunition, Atmospherics.

Why only three? Because that’s all you need to start shooting long range!

 

Rifle

Zero range:

The ballistic solver needs a starting point. At what range did you zero your rifle? Now the question comes up; “Should I do a 100 yard zero or a 200 yard zero?” That’s a discussion for another article - NO FLUFF I promised in the beginning! (but do a 100 yard zero) *wink, wink*

Scope height:

This input determines the geometry between your line of sight and line of bore. This needs to be as accurate as possible but no need to get fancy. Use a caliper, a ruler or a Leatherman and get it to the closest ⅛ of an inch and you’ll be fine (unless you’re trying to be King of 2 Miles or something). This distance is measured from the centerline of your bore to the centerline of your scope.

 

Twist rate/direction:

This input determines your spin drift. This is another subject I could write an entire article on, but all you need to know is this: The direction of your barrel twist determines the direction your bullet will drift as it travels down range. The tighter the barrel twist, the more your bullet will drift in that direction.

Angle unit of optic:

I know this is not your rifle, but it is part of your rifle system. This input determines whether your ballistic solver output will be given to you in Milliradian (MIL) or Minutes of Angle (MOA). Whether you need MIL or MOA will be determined by your riflescope. Having a riflescope with MOA turrets and a ballistic solver that provides solutions in MIL doesn’t do you much good!

That’s it! Those are all the inputs a ballistic solver needs when it comes to your rifle.

 

Ammunition

185gr. RDF, etc.) Caliber: The ballistic solver needs your bullet diameter to expedite the process of finding your bullet within the bullet library. Example: Caliber = bore/bullet dimension. Both a 300 Win Mag and a 308 Winchester are .308 caliber, whereas a 7mm Rem Mag and a 28 Nosler are both .284 caliber.

Most ballistic solvers have a - “bullet library” that contains projectiles available in that caliber. For example, in the .284 caliber, the library is likely to contain dozens of options (i.e. Berger 168 gr. VLD Hunting, Hornady 180 gr. ELDM, Nosler 185gr. RDF, etc.)

 

Drag function and ballistic coefficient (BC): This is another topic worthy of its own article, but I’ll keep it simple. Look for “G1” or “G7” on your box of ammo and input the decimal number next to it in the ballistic solver. If it’s not on the box of ammo, Google your bullet’s BC. This will help the solver determine the trajectory curve of your bullet. That’s it! Just trust it! You can now skip to “Ammunition point 3”, but if you want a very elementary explanation on drag function, keep reading.

 

Drag function (G1 or G7) refers to which model of measurement you’re using in order to determine your trajectory curve. Here’s an elementary-level visual.

Drag Model	Based On	Accuracy	Best Use
G1	Older, blunt bullet shaped like artillery rounds	Good	Shorter Range
G7	Modern long-range bullet with boat tail	Better	Long Range
Dopper	Real radar data	Best	Long Range Precision or ELR

 

When in the ballistic solver, it asks you which drag model you want to use - select Doppler if it’s available, G7 as your second choice, and g1 as a last resort. Not all bullets have a Doppler file or have been measured using the G7 model. Use what’s available!

Regarding ballistic coefficient, the higher the number, the more efficient your bullet is at overcoming the effects of drag. It’s safe to say; the higher the ballistic coefficient number, the better the long-range bullet.

WHAT DOES THIS MEAN??

• All this does is help your ballistic solver calculate how efficient your bullet is, which will determine the shape of the bullet’s trajectory. Knowing this, the ballistic solver can tell you what to dial or hold on your optic in order to hit a target downrange.

 

Bullet weight:

This one is easy. If the box says 180 grain, then you will input “180”.

Bullet length:

<p">If your bullet was not in the “bullet library” then you’ll have to look up your specific bullet online to determine how long it is. This is not cartridge overall length. This is the length of the projectile itself. If you can’t find this information, pull a bullet out of the loaded case with a set of pliers and measure the bullet with a pair of calipers for best results.

Good news with the ammunition section! - Almost all ballistic apps have an extensive bullet library. Usually, after inputting the caliber, you’ll be able to find your exact bullet and cartridge in the bullet library. Therefore, you won’t need to input - Drag function/BC, Bullet weight, or Bullet length. All these things will be auto populated.

Muzzle velocity:

I saved this one for last in the ammunition section because it’s extremely important. This is specific to your rifle shooting a specific lot of ammunition. You can’t just use the estimated muzzle velocity provided on the box of ammunition if you’re expecting to achieve first round impacts at ranges, say, 600 yards and beyond. You need to chronograph your rifle to find your specific rifle/ammo combination’s velocity.

If you don’t have a chronograph, my rule of thumb is to take 50 FPS off of the advertised muzzle velocity on the box. The velocity numbers on the box are usually a little high. This is most likely because the manufacturer achieved their muzzle velocity using a long barrel - say 26” - in order to get a fast velocity printed on the box. So maybe use the -50 FPS rule if you have an 18-22’ barrel.

Again, that is it! That’s all you need to input into a ballistic solver when it comes to your ammunition.

 

Atmospherics

Elevation/Pressure:

The higher the elevation, the less atmospheric pressure there is. Therefore, most ballistic solvers auto populate the atmospheric pressure field once you’ve dictated what your elevation is above sea level. Why does this matter? Because, typically, the higher the elevation, the thinner the air, which means the lower you can aim or dial in order to impact the target. Bullets “feel” less resistance in lower air density environments.

Temperature:

Same concept here. The warmer the environment, the less dense the air. The colder the environment, the denser the air. Obviously, denser air creates more drag on the bullet.

Here’s the interesting part. The higher elevation, the less dense the air. Usually, though, the higher the elevation, the colder it is, and cold air is denser. Do you see how these can cancel each other out? Again, another deep diving topic, but thankfully most ballistic apps collect weather from the closest weather station (usually the closest airport) and automatically update your ballistics based on the current atmospherics. This doesn’t mean you should skip inputting your elevation, though!

Wind direction/speed:

Obviously, to hit a target at long ranges, we need to add the wind to the list of factors. Rule of thumb: Input the wind direction in clock method as best you can with the target always being at 12 o’clock. Guess the wind speed at 5, 10, or 15 MPH. If you can guess the wind within 5 MPH of actual wind speed - you’ll hit your target (unless you’re trying to shoot pop cans at 500 yards!)

What about humidity???

Forget it! Humidity’s impact on long range shooting is so minimal that it’s not even worth calculating. Try the following to illustrate my point: Input humidity at 1% and take note of your ballistic solution at 1000 yards. Now input your humidity at 100% at 1000 yards. Now you tell me if humidity matters. Forget about it!

 

Summary

With a ballistic solver, a decent rifle, and the above information, you should be able to get started shooting long range. Every point I’ve made here can be explained at a much deeper level, but I wanted to show you how simple it can be, rather than how difficult it can be! Always think of the glass as half full my friends!

Here’s the list without any explanation to really show how simple this is.