.17 Javelina (P.O. Ackley Data Vol. 2)

.17 Javelina (P.O. Ackley Data Vol. 2)

Appearing once again in P.O. Ackley’s writings — this time in Volume 2 — the .17 Javelina demonstrates the continued curiosity surrounding high-velocity, small-caliber wildcat cartridges. While the original concept was already covered in earlier texts, its reappearance reflects ongoing experimentation, refinement, and relevance among advanced reloaders and ballistic enthusiasts.

Building upon the foundation laid in Volume 1, the data and observations in Ackley’s second volume delve deeper into pressure behavior, case capacity optimization, and bullet performance at extended ranges. Though the .17 Javelina never achieved widespread factory adoption, its place in the handloading world was solidified through studies like these — where real-world results were documented meticulously, encouraging further use and innovation.

The cartridge itself remains the same in basic configuration: a .222 Remington Magnum case necked down to .17 caliber. This design offers a relatively generous powder column for such a small bore diameter, which enables impressive velocities with 20–25 grain projectiles. Ackley’s second volume includes experimental loads that emphasize how sensitive this cartridge is to powder type and case prep. Even slight inconsistencies can affect velocity spreads and group sizes — a reality that has made the .17 Javelina a favorite of precision reloaders who value control and customization.

One of the standout points in Volume 2 is the discussion of barrel fouling and throat erosion, both of which are concerns when pushing very light bullets at extremely high speeds. The .17 Javelina was not immune to these issues, and Ackley’s notes highlight the need for diligent cleaning and proper barrel break-in. His observations also suggest that the right barrel twist — often 1 in 10 or 1 in 9 — plays a vital role in maximizing stability, especially for longer projectiles used in windier conditions.

While modern cartridges like the .17 Remington and .17 Hornet have taken center stage in the commercial market, the .17 Javelina continues to represent a uniquely customizable option for handloaders who enjoy working with classic wildcats. The fact that it required no more than resizing .222 Remington Magnum brass (when available) made it relatively accessible for those already versed in cartridge conversion and case forming.

Those who shoot the Javelina today often do so with a sense of reverence. It’s not just about the ballistics — it’s about carrying forward a piece of ballistic history. Rifles chambered for this cartridge are typically custom builds, and dies must be specially ordered or located through secondhand sources. Still, the payoff is real: sub-MOA groups, reduced recoil, and stunning varmint performance at distances that most rimfires would struggle to reach.

As a result, the .17 Javelina — especially as outlined in Ackley’s second volume — has earned a place as one of the more refined, though underappreciated, wildcats of its time. It serves as a reminder that some cartridges exist not for mass production, but for the satisfaction of hand-tuned excellence.

Source: Wolfe Publishing