If an Animal’s Drop-to-the-Shot Reaction from “Shock” is Luck-of-the-Draw, What Is the Terminal Performance Sure Bet?

By Scott Fletcher

“Use P for Plenty”.   -  U.S. Army combat engineer universal rule.

The answer to the question posed by the article’s title is “a big-a$$ wound cavity”.

The article on “shock” introduced the claim that an animal’s drop-to-the-shot reaction strictly from “shock” was an infrequent luck-of-the-draw. The claim was based on an arbitrary shock definition from a nerd engineer with no medical credentials using physiological concepts virtually no one has seen in print. The real deal-breaker was likely the assertion that a bullet’s impact energy was not related/proportional to producing either “shock” or an attendant drop-to-the-shot reaction, as justified by data and observations contained in the 2023 management hunt report. The politest response from hard-core, velocity-freak-hunter skeptics was likely: “The boy ain’t right”.

Maybe so, maybe not. Regardless, a legitimate question posed by such a claim that requires a reasonable/pragmatic answer is: “If a drop-to-the shot reaction from “shock” is an infrequent luck-of-the-draw, why does an animal like a southern white-tail deer or impala consistently drop-to-the-shot when a high-velocity chambering launching a low-sectional-density bullet is used?” 

As discussed in the article on wound cavity volume, Colonel Townsend Whelen asserted that the killing power of a bullet depends on the size of the wound created. That assertion was proven in that article using wound volume and travel distance data from the 2023 management hunt report. This article presents the answer to the question just posed, justified by Colonel Whelen’s assertion and the data from the management hunt.

Both Graph 1 and Graph 2 from the 2023 management hunt report show trend lines logically indicating that the travel distance of a zebra shot through both lungs and the heart decreases with increased wounding, however determined. These trend lines were calculated by linear regression analysis, meaning that for the data points used, the computed trend line is a straight line. No attempt was made to extend these trend lines to estimate the travel distance at zero wounding, nor a wound volume at zero travel distance. A “zero” travel distance is considered to be a drop-to-the-shot reaction.

As explained in section 12.15 on page 63 of the report, an animal travel distance with zero wounding would be infinite/indeterminant. Consequently, mathematically and pragmatically correct trend-line extensions for both Graph 1 and Graph 2 would curve upward and to the left from the trend lines shown, and never intersect the travel distance axis. There were no data points to determine the curvature/shape of these graph trend lines, so no curved extensions were shown.

Similarly, trend lines were not extended to either the Total Bloodshot Tissue Volume (TBSTV) axis on Graph 1, or the Total Bullet Hole Volume (TBHV) axis on Graph 2 to indicate theoretical wound volumes corresponding to a “zero” travel distance/drop-to-the-shot reaction. No data from the hunt were obtained for a zebra dropping to the shot simply from wounding without the interpreted effects from “shock” to conclusively support these extensions. However, the computed correlation coefficient for both trend lines is greater than -0.9, indicating a very-good-to-excellent correlation between significant, boiler-room wounding and travel distance. The combination of the field and wounding data, applied mathematics, and Colonel Whelen’s assertion that the killing power of a bullet depends on the wound size indicates that straight-line extensions of the trend lines shown on these graphs to these wounding axes would be pragmatic and reasonable. Such extensions would identify a potential wound volume associated with a “zero”, drop-to-the-shot travel distance that was conceptually possible.

An extension of the trend line to the wounding required to produce a “zero”, drop-to-the-shot travel distance is identified on a modified Graph 1, identified as Graph 1M. This trend line extension indicates the inferred TBSTV required for both lungs and the heart to conceptually produce a drop-to-the-shot reaction would be about 670 cubic inches (10,972 cc). As shown on the graph, solving the trend line’s equation for “0” travel distance (TD) also results in a TBSTV of 670 cubic inches. Similarly, solving Graph 2’s trend line equation for a “0” (drop-to-the-shot) travel distance (TD) results in a TBHV of about 198 cubic inches (3,243 cc).

The shortest travel distance for all zebras shot through both lungs and the heart was 41 yards (37 m) for Zebra Z-5. As identified in Table 4 of the hunt report, the total bloodshot tissue volume (TBSTV) recorded for Z-5 was about 440 cubic inches, comprised of a total lung bloodshot tissue volume (LBSTV) of about 342 cubic inches and a heart bloodshot tissue volume (HBSTV) of about 98 cubic inches. The total bullet hole volume (TBHV) recorded for Z-5 was about 131 cubic inches, comprised of a total lung bullet hole volume (LBHV) of about 119 cubic inches and a heart bullet hole volume (HBHV) of about 12 cubic inches.

Both the use and magnitude of these wound-volume “numbers” are, admittedly, difficult to relate to and do not appropriately portray the visual reality of the actual wounding produced in the boiler room of Zebra Z-5. This reality is identified in Photo 1 that shows the wounding of Z-5’s near-side lung, and in Photo 2 that shows wounding of Z-5’s heart and far-side lung. Photo P-55 from the report shows the free-blood flow produced by this wounding, streaming from the bullet’s entrance hole. This flow was continuous for approximately five minutes. As indicated by the magnitude of the wounding “numbers”, these photos all appropriately represent the jaw-dropping wound carnage that was produced in Z-5’s boiler room. The observed wounding, with attendant wound-cavity-volume “numbers”, is considered demonstrably representative of the resultant minimal, 41-yard travel distance.

Extension of the trend lines of both Graph 1 and Graph 2 result in theoretical wounding volumes required to produce a “zero”, drop-to-the-shot travel distance that are approximately 50% greater than the actual wounding determined for Zebra Z-5. Conceptual visualization of wounding that is 50% greater than that depicted in Photo 1 and Photo 2 can be reasonably assessed as capable of producing such a drop-to-the-shot reaction.

The intent of the wound-volume “numbers” and the photos is to demonstrate that an animal’s drop-to-the-shot reaction can be reasonably expected to occur when the wound volume in the boiler room is sufficiently large enough to simply destroy/debilitate most of the affected vital organs. Such wounding that simply overwhelms an animal’s vital organs certainly occurs on a ground hog when shot with a 50-grain, 22-caliber bullet fired from a 22-250, and on a coyote (or a jackal) when shot with a 75-grain, 6 mm bullet fired from a 243 Winchester. Likewise, it is not difficult to envision wounding to the boiler room that simply overwhelms a southern white tail or impala when shot with a 30-caliber, 150-grain frangible cup-and-core bullet fired from any magnum chambering. The logical implication of all these examples is that progressively larger animals can be expected to require a progressively larger/more powerful cartridge capable of producing a progressively larger wound cavity volume in vital organs to enable a drop-to-the-shot reaction.

The zebras identified for inclusion in Graph 1 and Graph 2 all had common wounding in both lungs and the heart. The travel distances obtained are thus dependent on the cumulative wound volume of these combined vital organs. Had only both lungs been breached, travel distances would logically be greater because the heart was not affected. As a consequence, each species can be expected to have a unique wound cavity volume for the specific vital organs or combination of vital organs breached that produces a drop-to-the-shot reaction.

Based on the previous examples, the management hunt data, and Colonel Whelen’s assertion that the killing power of a bullet depends on the wound volume it creates, a consistent, drop-to-the-shot reaction is dependent on both the species being hunted and a sufficiently large wound volume produced in a specific vital organ or a combination of vital organs that simply overwhelms them. Such a conclusion explains why the wound volume in the relatively small lungs of a 150-pound (68 kg) deer or impala from passage a 30-caliber, 150-grain bullet launched from a magnum chambering can cause a drop-to-the-shot reaction, but the same wound volume from the same bullet and chambering combination in the larger lungs of a 650-pound (295 kg) zebra will likely result in an extended travel distance rather than a drop-to-the-shot reaction.

Selecting a species-specific cartridge intended to max-out the wound cavity volume in a specific vital organ or combination of organs thus becomes the “sure bet” to reduce travel distance after the shot, including a potential drop-to-the-shot reaction. The occurrence of “shock” then becomes a sidebar issue, simply icing on the wound-volume “cake” afforded by an appropriate cartridge selection.