Dr. Ed Ashby® Reports

Index of Dr. Ed Ashby's Arrow & Broadhead Penetration Reports -If you have never read Dr. Ashby's reports, you're in for a treat. They're like a good novel that you just can't put down, the content is intense. As you read you'll experience many "a-ha!" moments. Things you have seen and experienced will start to make sense. You may want to bookmark this page as your gateway into the portal of what really happens when arrow and broadhead meet hide, bone, gristle, and meat.

We have all of Dr. Ed Ashby's reports to date for you. As he releases more, we'll have them posted here. Here at GrizzlyStik, our roots are in traditional archery so we find it interesting this Dr. Ashby has always used both longbows and compound bows in his testing. Traditional bowhunters embraced the EFOC, heavy arrow, and heavy broadhead idea early on, but lately compound shooters all over the world are using our GrizzlyStik carbon arrows and our GrizzlyStik single-bevel broadheads for the largest of game with results that are becoming legendary. Some bowhunting camps in Africa now insist that if you're going to bowhunt with them, you'll be using a broadhead like the GrizzlyStik Ashby 315.


2021 Case Study - Cape Buffalo

July 2021 case study by ABF and PHASA representatives of ten popular two-blade broadheads tested on Cape Buffalo in South Africa

2019 UPDATE - Ashby's Top 12 Arrow Penetration Enhancing Factors

The Penetration Enhancing Factors

Ashby's Top 12 Arrow Penetration Enhancing Factors

Dr. Ashby's Top 12 - Ranked

Dr. Ed Ashby Getting an Edge on Success

Hemorrhaging Flow Chart

Ashby Broadhead Study

What makes a Lethal Broadhead?

Ashby on Single Bevel Broadhead

Why Single Bevel Broadheads?


Ashby On EFOC (Extreme Forward of Center)

Understanding and Applying FOC

Ashby Ultimate Hunting Arrows

Big Game ~ Big Arrows

Ashby On Momentum, Kinetic Energy, & Arrow Penetration

(And What They Mean To the Bowhunter)

Ashby's Arrow Lethality Study

Results In Graph Form

Papua New Guinea Bows and Arrows Study

And You Think You're Arrows Are Heavy


It's Hard to Argue with Facts & Figures -Starting in 1981, while working as a PH in Zimbabwe, Dr. Ed Ashby was recruited by the Mkuzi Game Reserve head Game Ranger Tony Tomkinsonto assist in a bowhunting research study. At the time bowhunting was not legal in South Africa. The government commissioned a study to determine if African game could be ethically and humanely harvested with the bow and arrow.


Four years later, Dr. Ashby and his team published what has come to be known as the "Natal Study." The research was based not on scientific methods but outcome-driven research. Arrow penetration tests were conducted on hundreds of freshly culled animals and results were meticulously recorded and documented. In 1986, based on the Natal Study, the South African government legalized bowhunting. Legalization in South Africa soon opened legal bowhunting in many other Sub-Saharan countries. The Natal Study was the definitive document used to successfully lobby for bowhunting legalization.

Ashby On Arrow Lethality Part 1
The Need for Knowledge

Ashby On Arrow Lethality Part 2
Broadheads - The Natal Study

Ashby On Arrow Lethality Part 3
Turning "Hits" into"Kills"

Ashby On Arrow Lethality Part 4
The Physics of Arrow Penetration

Ashby On Arrow Lethality Part 5

Predicting Arrow Penetration on Real Animals

"In bowhunting, there is no such thing as overkill?" ~ Dr. Ed Ashby


Ashby 2008 Update Part 1

Heavy Bone Threshold

Ashby 2008 Update Part 2

Commonly Used Arrows

Ashby 2008 Update Part 3

Arrow Force and The Heavy Bone Threshold

Ashby 2008 Update Part 4

Threshold of Arrow Mass

Ashby 2008 Update Part 5

Meaningful Arrow Comparisons

Ashby 2008 Update Part 6

Quantifying Arrow FOC on Penetration

Ashby 2008 Update Part 7

Ultra-EFOC and Arrow Shaft Structural Integrity




Dr. Ashby displays a cutaway of the Asiatic Buffalo's front shoulder to show what bowhunters are up against and why the "heavy bone threshold" is so important when hunting dangerous game.

Ashby 2007 Update Part 1

Will it Ever End?

Ashby 2007 Update Part 2


Ashby 2007 Update Part 3

Testing Internal Footings

Ashby 2007 Update Part 4

Establishing a Baseline

Ashby 2007 Update Part 5

Extreme FOC's Demonstrated Advantage

Ashby 2007 Update Part 6

Current Broadhead Testing

Ashby 2007 Update Part 7

Angle of Attack

Ashby 2007 Update Part 8

Penetration is Paramount

Ashby 2007 Prologue

Understanding FOC



"No bowhunter has ever lost an animal because his arrow penetrated too much!" ~ Dr. Ed Ashby



Ashby 2005 Update Part1

BroadheadTip Design and EdgeBevels

Ashby 2005 Update Part 2

Weight Forward of Center (FOC)

Ashby 2005 Update Part 3

Broadhead Performance Update

Ashby 2005 Update Part 4

Buffalo Arrows

Ashby 2005 Update Part 5

Summary Overview: Trends, Tendencies, FAQ, and Comments

Ashby 2005 Update Part 6

The Heavy Bone Threshold


Dr. Ed Ashby inspected a Water Buffalo scapula during the testing process. For over 30 years, Doc has been compiling arrow penetration on real animals (not ballistic jelly or 55-gallon drums) and sharing his findings for free. The good Doctor and GrizzlyStik have always welcomed peer review and critique of the research findings - BUT - if you don't have 30 years of documented research (we can review), you're just espousing your opinion. Publish it if it's scientific and we'll review it.


Ashby 2004 Update Part 1

Testing66 Different Types/Styles/Configurations of Broadheads

Ashby 2004 Update Part 2

Data Relative to Arrow Shafting, Shot Placement, and Shooting Angles


"When heavy bone is hit an arrow of approximately 650 grains total mass penetrates the bone with a significantly higher frequency than an arrow below this total weight." ~ Dr. Ed Ashby



Ashby 1987 Part 1

Broadhead Performance

Ashby 1987 Part 2

Broadhead Performance Continued

Ashby 1987 Part 3

Broadhead Performance Continued

Ashby 1987 Part 4

Broadhead Performance Continued

Ashby 1987 Part 5

Broadhead Performance Continued



PODCAST with Dr. Ed Ashby & GrizzlyStik 



The MeatEater Podcast with Dr. Ed Ashby, Garrett Schlief & Todd Smith


Live to Hunt & Fish Podcast with Dr. Ed Ashby & Garrett Schlief Part 1


Live to Hunt & Fish Podcast with Dr. Ed Ashby & Garrett Schlief Part 2


Journal of Mountain Hunting Podcast with Dr. Ed Ashby & Garrett Schlief


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