This website contains original, AI-free content describing how an expanding hunting bullet’s general (generic) design and impact velocity both produce and control its wounding, how such wounding can be modeled with a gel test, and how gel-test metrics and their values empirically predict likely field performance. These wound-cavity based terminal performance concepts and metrics are applied to common hunting scenarios using worked example problems to demonstrate how hunters can confidently select both cartridges and cartridge bullets that meet their field-performance objectives.  

U.S. Army ordinance and medical corps experts have determined the wound cavity volume produced by a bullet in vital organs is the sole basis of its lethality. Quite simply, more wound cavity volume produces a shorter time to death. However, these experts did not provide a method for applying wound cavity concepts to predict the field wounding, penetration, and meat damage produced in an animal by an expanding hunting bullet. A personal analytical model based on testing expanding bullets in synthetic gel as well as an empirical equation are presented in this website that enable such empirical terminal performance predictions.

Passage of a bullet through testing gel produces a simulated wound cavity. A personal analytical model, called the Guppy, identifies the modeled cavity volume and other key metrics that can be measured/calculated from the gel-test block(s). The wounding-mechanism concepts represented by these gel-test metrics are grounded in engineering mechanics and have been confirmed by both repeated personal gel testing and field terminal performance data obtained on a self-funded zebra management hunt. The Guppy analytical model can be accessed by clicking on the “Guppy Model” tab on this page’s header. The metrics identified in that model are mathematically defined, and accessed by clicking on the “Guppy Tech” tab.

A metric is a classification category that has interpretive context applied to its value. Articles found by clicking on the “Terminal Performance Articles” tab demonstrate that traditional terminal performance metrics, such as a bullet’s impact energy, weight retained, and mushroom diameter, are either entirely false or can be misleading for either predicting or evaluating a bullet’s terminal performance based on field and skinning-shed data obtained from the management hunt. In contrast, these same field and skinning-shed data show Guppy metrics and metric values empirically predicted field wounding, penetration lengths through an animal’s thoracic cavity, and the qualitative degree of bloodshot meat. The complete, 84-page report with conclusions, supporting gel-test and field data, and explanatory photos can be accessed by clicking on the “2023 Hunt Report” tab.

The zebra management hunt also confirmed the validity of a personal empirical equation that estimates the non-dangerous game weight that can be efficiently harvested by any cartridge-bullet combination based on the bullet’s weight and impact velocity. The empiricism’s derivation is presented in eBook Chapter 19, accessed by clicking on the “eBook” tab on this page’s header.

Guppy metrics are uncommon. However, personal gel testing has indicated a bullet’s relative degree of wounding, penetration, and potential meat damage can be estimated based on its general (generic) design and impact velocity. These bullet-specific generalities can be applied in conjunction with the empirical equation to select a bullet with desired terminal performance characteristics based on a specific hunt scenario. This method is introduced in three articles discussing cartridge selection, found by clicking on the “Terminal Performance Articles” tab.

Stalking both trophy and management-hunt animals in Africa identified personal equipment and technique challenges that needed to be met to increase the odds of a recovered animal. This website also contains articles about generic equipment, shooting techniques, and other selected topics based on personal “lessons learned”, applicable for any hunting scenario for any animal on any continent. These articles are accessed by clicking on the “Hunt-Related Articles” tab.

To all hunters, I wish you good hunting and recovered animals.

Scott Fletcher