By: Wade Nolan Bowhunting Biologist
The late Steve Jobs was a master at thinking outside the box. Because it hadn't been done before was all the motivation he needed to go in that new direction. Steve thought, why follow everyone down the same rut. He had a great point and one that I'm going to parallel while examining a new broadhead design. The approach may be revolutionary but does it make sense?
Is there room for improvement in a broadhead? Statistics say that bowhunters recover 50% of the deer they hit…What do you think?
It is a mechanical…nothing new there. It is a two-blade system…nothing new there. It employs the simplest of all mechanical principals to deploy the blades…nothing new there. A dead guy, Archimedes, discovered this principle before sliced bread. What is revolutionary are the problems it solved by incorporating some focused engineering. The fact that a missile engineer, who is also a bowhunter, designed it may have helped. It simply solves performance issues everyone has been putting up with.
Angled plywood is the most representative test medium for angle penetration tests. It is critical to get the angles correct. We had an engineer present consulting us on broadhead impact angles. Most broadheads performed poorly, except one.
Here are the basics of its performance. It is engineered with a tip forward design that eliminates deflection issues. In a series of tests in a shooting lab we discovered that it is unparalleled in its ability to dig into an angled target and maintain a linear flight path. We used angled plywood and demonstrated that no mechanical even comes close to its performance on an angled target. This is important on a steep quartering whitetail.
Real results come from authentic testing. We varied the test subjects from steel drums to gelatin and got uniform results. Most broadheads failed. One didn't.
In ballistic gelatin testing we discovered that it out penetrated the other popular mechanicals and cut more tissue in doing so. Our tests involved setting up authentic shots. We used green deer hide, whitetail rib panels and shoulder blades. We also used steer shoulder blades, cold rolled steel drums and plywood. The ballistic gelatin is military spec and the camera is special. It is a$75,000 digital slow-motion camera. Our results are real and repeatable. Most mechanical broads failed…yours included.
One of the most telling results involved something we weren't specifically testing for. Although blade integrity was on our list of dynamic tests, what we learned concerning the blade performance and condition upon entering an animal was a side benefit of the testing regime. We opened the door on something that is never discussed in broadhead forums, blade sharpness “after penetration". This sharpness issue was the criteria that were most striking. Here is what we learned.
As base knowledge let me state that blade sharpness, once the broadhead gets to its real job; cutting internal organs tissue and vessels, is the foundation of broadhead effectiveness. Dull blades result in minimal hemorrhaging and loss of game.
Our testing documented that there is critical net loss of blade sharpness as a blade passes through bone. Each of the three broadheads I am about to show you passed through either a deer shoulder blade or deer ribs. In two of the broadhead designs, the blades were wide open (fully deployed) prior to passing through hide and bone.
One broadhead is known for its ability to blow through bone and the other a slip-cam design that opens on impact where the blades have to cut through hair hide, some meat then bone before getting to the vital internal organs. Let's see what happened during the testing to these two broadheads.
This quality fixed blade broadhead has taken a lot of game and is the choice of many bowhunters. Look closely at the condition of the blades cutting edge's. This head killed a Texas boar. What is your assessment of the blade condition and sharpness after quartering through boar ribs?
The first, a three-blade fixed blade head made it through the hair, hide and ribs with no trouble but look what happened to the sharpened blade edge during the trip to the internal organs. The cutting edges are bent over, wavy, nicked, and totally compromised.
The cutting edge is somewhere between butter knife sharp and dull at this point. The problem is that cutting hair, hide and puncturing a shoulder blade isn't a critical injury for a whitetail. You must cut internal organs to dispatch a deer. All this damage occurred on the blades trip through the non-essential hair, hide and bone. By the time it got to the vital organs, it had been embarrassingly dulled.
Now let's look at the well marketed, slip-cam design head that opens on contact. Testing revealed that it indeed did open to it's full 2-inch wide cutting diameter before passing through the deer hair, hide and rib. In this test the blades didn't fall off while going through the ribs, they cut right through. But there is a problem.
This open on contact slip-cam blade passed through whitetail ribs during our ballistic gelatin testing. Look carefully at the blade's leading edge. Does that meet your standards?
The blades are both twisted and cutting edge no longer faces forward at a 90-degree angle. However, even more importantly the blades leading edges were rolled over and dulled by the encounter with the bone. At least 40-50% of the two inches of cutting blade is damaged and unable to perform its job. At this point you're down to one inch of crooked blade as the broadhead gets to the important zone…internal organs and vessels.
Are you ready for a solution? This next broadhead design addresses this issue with a two-step cutting design. In that over 85% of bowhunters hunt from trees we can assume that entry wounds are above the centerline of a deer angling downward. Therefore, the exit wound and not the entry wound is the one that generates the blood trail. Using up foot-pounds of energy and compromising blade sharpness to make a huge entry wound is of little value.
Look at the entrance hole. It was a steep quartering shot almost straight down. The exit was impressive as are the antlers on this public land Ohio buck.
Out testing revealed that getting razor sharp blades into the vital organs is job #1. The challenge was that the broadhead had to get through hair, hide and bone to arrive there. Once the broadhead engineer knew what the challenge was he designed his way to a solution. Existing science was part of the solution.
There is solid research conducted by Dr. Ed Ashby in Africa, concerning the benefit of a chisel design of a cutting edge as it relates to cutting hide and especially bone. Ashby states, “The splitting of bone, (as opposed to cutting a blade sized hole through it with a traditionally V-sharpened blade) is a desirable feature in a broadhead design." Ashby goes on to explain that a single bevel chisel cutting edge splits bone and does so by using an arrow's rotational energy combined with wedging action of a chisel design. By doing so, more penetration is the result. A single bevel blade design is by design more efficient at getting through bone. Ever look at a wood chisel, only sharpened on one side. That's what Dr. Ashby is talking about.
What great scientific information. Dr. Ed's research proved that single bevel blade design blew through bone and increased penetration. This important factor was engineered into this next test broadhead for step #1 of the two step approach. The broadhead is a Swhacker. Let's go to the test lab.
Wade Nolan examines the results of a ballistic gelatin test where the arrow shot through deer hide, bone and gelatin.
By shooting into ballistic gelatin and observing the result with high-speed camera, we unveiled the answer. It was the revolutionary two-step deployment design that allowed the one-inch bone single-bevel chisel blades to efficiently cut through the hair, hide bone making a 1-inch + entry wound. Then, upon entering the clear Gelatin (internal organs) the big 2-inch wide virgin sharp cutting blades deployed and pushed through the Mil. Spec. Gelatin like a hot knife through butter.
Bone Chisel blades- These unique and rugged bone splitters' are called Bone Chisel Blades. The two chisels are actually reverse beveled to compliment the arrows rotation as bone is split. The single sided bevel edge paves the way for the big cutting blades and preserves the virgin edges for cutting internal organs.
Upon examination, we discovered that the inch-wide “Bone Chisel Blades" held up to the task of cutting hide and then splitting through rib bone. Then the pressure on the bone-chisels instantly deployed the two giant cutting blades via the simplest of all means (the lever design-like scissors use). The deployment system is totally dependable. Most importantly there is no blade damage when the broadhead gets to job #1. The big cutters are factory sharp as they deploy on internal organs.
This actual test head that passed through Deer hair, hide, rib bones and penetrated ballistic gelatin. Note the Swhacker wide cutting blades. They are in virgin cutting condition. Big cutting blades were factory sharp as they deployed in the gelatin. Note the intact Bone Chisel blades that split through the ribs. One is slightly bent but intact. Swhacker engineering at work.
Then, it gets better. By conserving energy other broadheads waste by cutting a wide high entrance hole, the Swhacker uses that reserved energy to cut tissue, internal organs and then to make a giant low exit wound.
Here is the business end of the new broadhead that solved the issues common to mechanicals and many fixed blades. Meet S. W. Hacker.
That's revolutionary. That's the first engineered answer to broadhead design in a decade…and it doesn't smell like horse pucky. A radical two-step design that blows through bone then deploys the big slicers. That's thinking outside of the box. That's engineering success into the hunt. That's the new Swhacker.
For more go to: Swhacker Broadhead