ATA and IBO speeds are two distinct, standardized methods used to measure and compare the velocity of an arrow shot from a bow, providing common benchmarks for manufacturers and archers.
Understanding Bow Speed Standards
In the world of archery, comparing the performance of different bows, particularly their speed, requires a consistent method. Since various factors like draw weight, draw length, and arrow weight directly influence arrow velocity, standardized testing procedures were developed to allow for fair comparisons. The two primary standards you'll encounter are those set by the International Bowhunting Organization (IBO) and the Archery Trade Association (ATA).
IBO Speed: International Bowhunting Organization Standard
The International Bowhunting Organization (IBO) established a standard for measuring bow speed that typically results in the highest reported velocities. This standard is designed to showcase a bow's maximum potential speed under specific, demanding conditions.
- Draw Weight: 80 pounds (with a tolerance of +/- 2 pounds)
- Draw Length: Maximized for the bow
- Arrow Weight: 400 grains
Manufacturers often advertise IBO speeds to highlight a bow's raw power and speed capabilities, as these parameters push the bow to its peak performance.
ATA Speed: Archery Trade Association Standard
The Archery Trade Association (ATA) provides another common standard for measuring bow speed. The ATA standard reflects a more common setup for hunting or recreational archery, using parameters that are generally more practical for the average archer.
- Draw Weight: 70 pounds (with a tolerance of +/- 0.2 pounds)
- Draw Length: 30 inches
- Arrow Weight: 350 grains
Because the ATA standard uses a lower draw weight and a fixed, often shorter, draw length compared to IBO, the resulting speeds are typically lower. However, ATA speed often provides a more realistic expectation of a bow's performance for many users.
Key Differences at a Glance
The most straightforward way to differentiate between ATA and IBO speed measurements is by looking at the specific testing parameters:
| Feature | IBO Speed Standard | ATA Speed Standard |
|---|---|---|
| Organization | International Bowhunting Organization | Archery Trade Association |
| Draw Weight | 80 pounds (+/- 2 pounds) | 70 pounds (+/- 0.2 pounds) |
| Draw Length | Maximized (set to the longest available for the bow) | 30 inches |
| Arrow Weight | 400 grains | 350 grains |
| Reported Speed | Generally higher | Generally lower |
| Purpose | Benchmarking maximum speed potential | Benchmarking speed in common, practical settings |
Why Do These Standards Matter?
Understanding ATA and IBO speeds is crucial for archers and hunters for several reasons:
- Informed Purchasing Decisions: These standards allow you to compare bow models fairly. If one bow advertises an IBO speed of 350 FPS and another an ATA speed of 320 FPS, you can't directly compare them without knowing the underlying standards.
- Realistic Expectations: An IBO speed rating is often the absolute peak a bow can achieve. Your actual arrow speed in the field will likely be lower, as you may use different draw weights, draw lengths, or arrow weights. ATA speeds might offer a more practical baseline for many archers.
- Personal Setup Customization: Knowing these standards helps you understand how changes to your bow's draw weight, draw length, or arrow weight will impact your arrow's velocity relative to the advertised speeds. For instance, using a heavier arrow than the standard or a shorter draw length will reduce your actual speed.
- Consistency: The very existence of these standards ensures a level playing field for bow manufacturers, encouraging innovation while maintaining a transparent way to report performance.
