About
Peteward Ballistics Calculator (V2.08) is a free, browser-based JavaScript tool tailored for archers and bowhunters who want precise ballistic data for their setups. Built around models from "Exterior Ballistics of Bows and Arrows" by W.J. Rheingans, the calculator accepts inputs such as arrow speed, arrow weight, fletching length and height, shaft diameter, and shaft length to produce a comprehensive ballistic table at 10-yard increments from 0 to 100 yards. The tool supports both feather and plastic vane fletching types, and calculates key metrics including vertical drop (in inches), arrow speed (fps), kinetic energy (ft-lbs), and momentum (lb-sec) at each distance. It can also estimate arrow speed from bow specifications like Stored Energy-to-Peak Draw Force ratio, Bow Efficiency, Virtual Mass, and Static Hysteresis — data obtainable from archery magazine bow tests. Additionally, for quick kinetic energy calculations, only initial velocity and arrow weight are required, making it useful for quick field estimates. The tool includes helpful notes on accounting for accessories like nocks, kisser buttons, peep sights, and string silencers when calculating total arrow weight. It also links to a companion graphing trajectory calculator for visual trajectory analysis. Ideal for bowhunters, competitive archers, and archery enthusiasts who want data-driven tuning insights.
Key Features
- Full Ballistic Table Generation: Produces a 0–100 yard table showing vertical drop, arrow speed, kinetic energy, and momentum at every 10-yard increment.
- Fletching Type Support: Accepts both feather and plastic vane fletching inputs (length and height) for accurate drag modeling.
- Arrow Speed Estimation from Bow Specs: Can estimate arrow speed using technical bow data such as stored energy, bow efficiency, virtual mass, and static hysteresis.
- Quick Kinetic Energy Calculation: Requires only initial velocity and arrow weight to compute kinetic energy at a given speed — no full setup needed.
- Accessory Weight Notes: Guides users on accurately accounting for nocks, kisser buttons, peep sights, and string silencers in total arrow weight.
Use Cases
- Bowhunters dialing in their equipment before deer or elk season by calculating arrow drop at various distances.
- Archers fine-tuning arrow selection by comparing ballistic tables for different arrow weights and speeds.
- Archery coaches and students studying the physics of arrow flight and exterior ballistics.
- DIY archers building custom setups who need to estimate performance before shooting through a chronograph.
- Equipment reviewers or magazine contributors verifying arrow energy and momentum figures from bow test data.
Pros
- Completely Free: No cost, no registration, and no software to install — runs entirely in a web browser.
- Physics-Based Accuracy: Calculations are grounded in established exterior ballistics models from published archery research, providing reliable trajectory data.
- Covers Key Metrics: Outputs all the most important ballistic figures — drop, speed, energy, and momentum — in one convenient table.
Cons
- Outdated Browser Requirements: Originally built for IE4+ and Netscape 4.08+; the interface is very dated and may have compatibility issues with modern browsers.
- No Visual Output: The tool only produces text-based tables; graphical trajectory plots require a separate linked calculator.
- Limited Interactivity: Minimal user guidance and no save or export functionality — results must be manually recorded.
Frequently Asked Questions
What information do I need to generate a ballistic table?
You need your arrow speed (fps), arrow weight (grains), fletching length and height (inches), shaft diameter, and shaft length. Select your fletching type (feather or plastic vane) and click 'Calculate Table'.
Can I calculate kinetic energy without filling out the full ballistic table?
Yes. For a quick kinetic energy estimate at a given speed, only your initial arrow velocity and arrow weight are required.
Where do I get technical bow data like stored energy or bow efficiency?
These figures are published in archery magazines such as Bowhunting World (by Norb Mullaney) and Bow and Arrow Hunting Magazine (by Emory J. Loiselle), which conduct standardized bow tests.
How do I determine shaft diameter for aluminum arrows?
For aluminum arrows, the first two digits of the shaft designation represent the outside diameter in 64ths of an inch. For example, a 2317 shaft has a diameter of 23/64" or approximately 0.359 inches.
Is the calculator accurate at longer distances?
The author notes results appear accurate out to at least 30 yards based on personal testing. Longer-distance accuracy depends on how precisely bow and arrow specs are entered.
