In my reading, I stumbled across an interesting study that has some answers to the question below.
A primitive archery specialist and author, Ryan Gill came to a clear conclusion after taking over 60 head of game with primitive archery setups using what would be considered exceptionally low energy by today’s standards. As you read, keep in mind his kills were made using stone points, wooden arrows, and shooting heavy 50-60lb wood traditional bows at a mix of hogs and deer in Florida. Here is the summary.
His results indicated:
The most effective primitive arrow builds used less than one inch wide points (often pushing the legal minimum for the area), had a smooth transition from the point to the shaft, carried 25 ft-lbs or more K.E. and were used to kill animals 15 yards or closer.
He developed threshold and objective values for arrow energy from his results
-His recommended minimum is a 400-grain arrow moving 150 fps.
-His ideal hunting setup is 160+ fps with a 400-500 grain arrow and a narrow broadhead.
Some study limitations
-Stone points often fail on bones other than the ribs. This limited shots to broadside and quartering away.
-When using primitive bows, the draw weight required to meet the 25 Ft-Lbs energy threshold was 50-60 lbs.
-Small stone points are inherently light, which limited FOC comparisons in the study.
Other tests and data
Animal movement
Using high-speed film, they documented deer movement and reaction time. This data drove their use of lighter and faster arrows. The lightest successful arrow in the study was around 360 grains.
.16 Seconds to start moving
.28 seconds to fully load their legs
.36 seconds to spring away.
Steel vs Stone points
Another test was completed to compare the force required to pierce hide with a stone point vs a more modern steel broadhead. The steel point required about ½ the force to penetrate.
The big takeaways
-When using less energy, mass, FOC, and energy are less important than minimizing point friction.
-His data showed a strong correlation between small points and better penetration.
-The lightest successful arrow in the study was 360 grains, and he saw some pass-throughs with 400-grain arrows. Many of these slipped between the ribs or only encountered ribs.
My personal notes
The book was obviously written by someone who spends most of their time outdoors doing things other than writing, and as such, it is a bit rough around the edges. If you are going to purchase the book for yourself, do so for the data rather than the reading enjoyment. I find other bowhunting works by authors like Roy S. Marlow more enjoyable to read.
The data present a clear case for the minimum energy required in a “Plan A” arrow. AKA shoot through the ribs broadside or quartering away. It does not provide any insight into energy thresholds or broadhead design for penetrating the shoulder and scapula.
Citation
In his book, he explicitly states that the information should be freely shared so long as it is properly documented.
Gill, Ryan, “The Secrets and Science of Primitive Archery Vol 1.” 2022.
other tags to help the search function
Low kinetic energy
Low momentum
Minimum energy
Low KE
“How much energy does it take to kill medium-sized game with a bow?”
A primitive archery specialist and author, Ryan Gill came to a clear conclusion after taking over 60 head of game with primitive archery setups using what would be considered exceptionally low energy by today’s standards. As you read, keep in mind his kills were made using stone points, wooden arrows, and shooting heavy 50-60lb wood traditional bows at a mix of hogs and deer in Florida. Here is the summary.
His results indicated:
The most effective primitive arrow builds used less than one inch wide points (often pushing the legal minimum for the area), had a smooth transition from the point to the shaft, carried 25 ft-lbs or more K.E. and were used to kill animals 15 yards or closer.
He developed threshold and objective values for arrow energy from his results
-His recommended minimum is a 400-grain arrow moving 150 fps.
-His ideal hunting setup is 160+ fps with a 400-500 grain arrow and a narrow broadhead.
Some study limitations
-Stone points often fail on bones other than the ribs. This limited shots to broadside and quartering away.
-When using primitive bows, the draw weight required to meet the 25 Ft-Lbs energy threshold was 50-60 lbs.
-Small stone points are inherently light, which limited FOC comparisons in the study.
Other tests and data
Animal movement
Using high-speed film, they documented deer movement and reaction time. This data drove their use of lighter and faster arrows. The lightest successful arrow in the study was around 360 grains.
.16 Seconds to start moving
.28 seconds to fully load their legs
.36 seconds to spring away.
Steel vs Stone points
Another test was completed to compare the force required to pierce hide with a stone point vs a more modern steel broadhead. The steel point required about ½ the force to penetrate.
The big takeaways
-When using less energy, mass, FOC, and energy are less important than minimizing point friction.
-His data showed a strong correlation between small points and better penetration.
-The lightest successful arrow in the study was 360 grains, and he saw some pass-throughs with 400-grain arrows. Many of these slipped between the ribs or only encountered ribs.
My personal notes
The book was obviously written by someone who spends most of their time outdoors doing things other than writing, and as such, it is a bit rough around the edges. If you are going to purchase the book for yourself, do so for the data rather than the reading enjoyment. I find other bowhunting works by authors like Roy S. Marlow more enjoyable to read.
The data present a clear case for the minimum energy required in a “Plan A” arrow. AKA shoot through the ribs broadside or quartering away. It does not provide any insight into energy thresholds or broadhead design for penetrating the shoulder and scapula.
Citation
In his book, he explicitly states that the information should be freely shared so long as it is properly documented.
Gill, Ryan, “The Secrets and Science of Primitive Archery Vol 1.” 2022.
other tags to help the search function
Low kinetic energy
Low momentum
Minimum energy
Low KE
