Free hunting tool
Rifle Ballistics & Long-Range Drop Calculator
A real G1 trajectory solver, not a lookup table. Enter your load, or pick a cartridge, for bullet drop, scope come-ups in MOA and MIL, wind drift, and retained velocity and energy at every range, corrected for altitude and temperature. Then see exactly how far your load stays lethal on real game, from whitetail and elk to kudu and buffalo.
Bullet weight (30–750)
From the box or a chronograph
G1 BC. G7 is more accurate for boat-tails.
Where the rifle is sighted in
Scope centre above bore
Full-value 90° wind
Uphill or downhill angle
Long-range & conditions (twist, Coriolis, atmosphere, truing)
e.g. 8 for 1:8
e.g. 0.264
For stability + spin
Blank = off
For Eötvös
Minor effect
Dialed a real come-up to hit at a known range? Enter it and we calibrate the model to your exact rifle and ammo, the way the pros do.
Come-up & drop chart
| Range | Vel | Energy | Drop | Up (MOA) | Windage | ToF |
|---|---|---|---|---|---|---|
| 50 yd | 2829 | 2666 | -0.2" | 0.4 | 0.2 | 0.05s |
| 100 yd | 2760 | 2536 | 0" | 0 | 0.4 | 0.11s |
| 150 yd | 2690 | 2411 | -0.9" | 0.6 | 0.7 | 0.16s |
| 200 yd | 2622 | 2290 | -3.1" | 1.5 | 0.9 | 0.22s |
| 250 yd | 2555 | 2173 | -6.5" | 2.5 | 1.1 | 0.28s |
| 300 yd | 2488 | 2062 | -11.2" | 3.6 | 1.4 | 0.34s |
| 350 yd | 2422 | 1954 | -17.3" | 4.7 | 1.6 | 0.4s |
| 400 yd | 2358 | 1851 | -24.9" | 6 | 1.9 | 0.46s |
| 450 yd | 2294 | 1752 | -34.1" | 7.2 | 2.2 | 0.52s |
| 500 yd | 2230 | 1657 | -44.9" | 8.6 | 2.4 | 0.59s |
| 550 yd | 2168 | 1566 | -57.5" | 10 | 2.7 | 0.66s |
| 600 yd | 2107 | 1478 | -71.9" | 11.5 | 3 | 0.73s |
Atmosphere
Elevation
Air temperature
How far does this stay lethal?
Retained energy against the guideline for each animal. Tap one for the full verdict.
Lethal range is where the load holds the guideline minimum energy for that class (800/1200/1800/2800 ft-lbs small/medium/large/heavy). A guideline built on published energy figures, not a rule. Bullet construction, shot placement and your local minimum-caliber laws matter as much as energy, especially on dangerous game. Always confirm your own zero and dope on paper.
This calculator is one tap away in the field, free, with your whole hunt.
It is built into the free hunter app, alongside everything you need on the hunt and after it. No app store, no cost, and it all works offline deep in the bush.
How accurate is it?
We validated the solver against published factory drop charts across the full spectrum of hunting cartridges. With a 100-yard zero, the drop, the number you actually dial, lands within a couple of inches of the factory data out to 500 yards, the range that covers the overwhelming majority of hunting shots. Bullet weight, ballistic coefficient and drag model are the inputs; the physics is the standard G1/G7 point-mass model.
| Load (100 yd zero) | Range | Our drop | Factory drop |
|---|---|---|---|
| .308 Win 168gr @ 2650 | 500 yd | -55.8" | -56" |
| .30-06 180gr @ 2700 | 500 yd | -52.5" | -52" |
| 6.5 Creedmoor 143gr @ 2700 | 500 yd | -49.7" | -51" |
| .300 Win Mag 180gr @ 2960 | 500 yd | -41.8" | -40" |
| .30-30 150gr @ 2390 | 300 yd | -22.3" | -21" |
For extreme range and match precision, use a G7 BC and, above all, true the calculator to your own confirmed drop (in the long-range settings). Truing calibrates the model to your exact rifle, velocity and conditions, which is how the best shooters and the top solvers get their last few percent. Always verify your dope on paper before relying on it in the field.
Reading the chart
Drop is where the bullet crosses relative to your line of sight: a positive number is above the aiming line, negative is below. Come-up is how much to dial or hold up to put the crosshair back on target, in MOA or MIL. Wind is drift from a full-value 90° crosswind at the speed you set. Energy is what the bullet still carries at that range, the number that decides whether it is enough for the animal.
Rows shown in amber are near or below the speed of sound (roughly Mach 1.1 and down), where many bullets lose stability and the numbers get unreliable. Treat that as the honest edge of your load’s reach.
Ballistics by cartridge
Pick your cartridge for a ready-made drop chart and its effective range on game.
Put this calculator on your site
Run a hunting blog, club or shop? Drop the ballistics calculator into any page, free. It stays up to date automatically. Just keep the HuntDesk credit link.
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<script>window.addEventListener("message",function(e){if(e.origin==="https://www.huntdesk.co.za"&&e.data&&e.data.type==="hd-arrow-height"){var f=document.querySelector('iframe[src="https://www.huntdesk.co.za/tools/ballistics-calculator/embed"]');if(f){f.style.height=e.data.height+"px";}}});</script>Method & sources
- The trajectory. A point-mass solver that steps the bullet downrange under gravity and aerodynamic drag using the standard G1 and G7 drag models, the same models factory ballistic tables and drag-function calculators (JBM, Hornady, Sierra) are built on. A bullet’s drag equals the reference projectile’s drag at the same speed and air density divided by the bullet’s ballistic coefficient. G7 is used for streamlined boat-tail bullets, where it is far more accurate downrange than a single G1 number.
- Truing. Enter a come-up you have actually confirmed on paper at a known range and the solver back-calculates a drag correction so the model matches yourrifle and ammo, absorbing the small errors in advertised BC and chronograph velocity. This is the same “truing” workflow used by Kestrel and Applied Ballistics, and it is what makes a calculator field-accurate.
- Long-range corrections.Spin drift (Litz approximation), horizontal and vertical Coriolis / Eötvös from your latitude and shot bearing, uphill and downhill shot-angle (the improved Rifleman’s rule), and a Miller gyroscopic-stability (Sg) check that warns when a bullet is under-stabilised for your barrel twist. These are the corrections the top-tier solvers include and most calculators ignore.
- The energy.Kinetic energy uses the standard sporting constant (7,000 grains per pound, 32.174 ft/s² for gravity): KE in foot-pounds = weight in grains × velocity in fps squared ÷ 450,436.
- Atmosphere. Altitude and temperature change air density and the speed of sound, following the International Standard Atmosphere, so drop and drift at 8,000 ft in the Karoo or the Rockies are right, not sea-level guesses.
- Wind.Crosswind drift uses the established lag-time method (drift = crosswind × the difference between actual and no-drag time of flight), the standard field approximation for a full-value 90° wind.
- “Enough gun” guidelines. Minimum terminal-energy figures by body size follow widely published hunting guidelines. They are a starting point, not a rule: bullet construction, shot placement and, on dangerous game, minimum-caliber law matter as much as energy.
- Cartridge figures are representative factory-load values; your box, barrel length and a chronograph reading of your own rifle are always the most accurate. Confirm your zero and dope on paper before relying on any chart in the field.
Frequently asked questions
How does a ballistic calculator work?
It steps the bullet downrange in tiny increments under gravity and aerodynamic drag, using a standard drag model (here the G1 model) scaled by your bullet's ballistic coefficient. At each distance it reads out remaining velocity, retained kinetic energy, the bullet's path relative to your line of sight, the scope come-up needed in MOA or MIL, and crosswind drift.
What is a ballistic coefficient (BC)?
Ballistic coefficient is a single number describing how well a bullet holds velocity against air drag. A higher BC means less drop and less wind drift downrange. The G1 BC is printed on most factory ammo boxes and bullet spec sheets. A bullet's drag equals the G1 reference projectile's drag at the same speed divided by that BC, which is why one number can stand in for the whole bullet shape.
What is the difference between MOA and MIL?
Both are angular units for dialing or holding elevation and windage. One MOA subtends about 1.047 inches at 100 yards; one mil (milliradian) subtends 3.6 inches at 100 yards, so 1 mil is about 3.4 MOA. Use whichever your scope turrets and reticle are marked in. This calculator shows both.
How much does altitude and temperature change my trajectory?
A lot at distance. Thinner air at altitude and warmer air both reduce drag, so the bullet drops and drifts less and stays supersonic further. This calculator adjusts air density and the speed of sound for your altitude and temperature using the International Standard Atmosphere, so mountain and desert dope is right rather than a sea-level guess.
How far is my rifle lethal on deer, elk or plains game?
It depends on retained energy at the animal. Widely used guidelines put light plains game and deer around 1,200 foot-pounds, large plains game and elk around 1,800, and heavy or dangerous game well above that. Enter your load and this calculator shows the range at which your bullet drops below the guideline for each class of game. Bullet construction and shot placement matter as much as the number.
What is the difference between a G1 and G7 ballistic coefficient?
G1 and G7 are two reference bullet shapes used to describe drag. A flat-based or short bullet is described well by a G1 BC; a long, streamlined boat-tail bullet is described far more accurately by a G7 BC, especially past 500 yards. This calculator supports both, pick the model your bullet's BC is quoted in (match and long-range bullets usually publish a G7 BC).
What is truing and why does it matter?
Truing calibrates the calculator to your actual rifle. You enter a come-up you have confirmed on paper at a known range, and the solver adjusts its drag so its predictions match your real drops. This absorbs the small errors in advertised BC and chronograph velocity and is how serious long-range shooters and the top solvers (Kestrel, Applied Ballistics) get their last few percent of accuracy.
Does this account for spin drift, Coriolis and shot angle?
Yes. In the long-range settings you can add your barrel twist for a spin-drift and gyroscopic-stability calculation, your latitude and shot bearing for the horizontal and vertical Coriolis (Eötvös) effect, and your uphill or downhill shot angle. These are folded into the come-up and windage columns, the same corrections the top-tier ballistic solvers apply for extreme-range precision.
Should I trust a calculator instead of shooting?
Use it to build a starting dope card and to compare loads, then confirm on paper. A calculator gets you very close, and truing it to a confirmed drop gets you closer still, but your exact velocity, zero, scope height and conditions decide the real numbers. Always verify your zero and true drops at distance before hunting.