How to Build a Hunting Arrow

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This is an introduction on building your hunting arrow. I will give some basic information on what to look at when building your hunting arrow. Then will give you links on other parts to put it all together for a complete and tuned hunting arrow.

When deciding on building your hunting arrow, you need to look at what you want for your set up. Hunting arrows can be built as light as 3 gr. per lb. for one bow manufacture, and up to ? gr. per lb. depending on what your hunting. For me and how I feel you should always look at building a arrow heavy enough to do the job when all
other factors are the same.

When picking your hunting arrow you need to look at what draw weight your shooting. This is where we see lots of mis informed archers. We have been taught by the archery world that speed is what we need. Speed is fine, but speed is not what kills. The arrow with mass is what kills. It’s important that we look at draw weight, lower draw weights with light arrows and speed will not give you consistent results every time.

There’s a article written on the QDMA sight by Bill Badgley. Click here to check it out; it’s a good quick read.
In the end, it recaps a good list of a average weight listed as grains of arrow weight per lb. This does not mean what is required, it’s just a suggestion by the writer on qdma.

  • 6 gr. per lb. for 70-lb.
  • 8 gr. per lb. for 60-lb.
  • 10 gr. per lb. for 50-lb.

Over the last 5 years I’ve realized that this recommendation is a close starting point but not what I would recommend. Based on my experience and data I have collected across the industry, I personally believe that you should start at least around:

  • 7 grains per lb. for 70 lb.
  • 8.5 to 9 grains per lb. for 60 lb.
  • 10 grains per lb. for 50 lb.

The simplest way to think about it is, you want to shoot the heaviest arrow you can, with the highest amount of FOC possible that has perfect flight, and a trajectory that you find satisfactory. But you must always have to remember physics. Heavy will always outperform light arrows. So you should always try to start at the weights listed above based on your draw weight.

   

Factors to consider when designing your hunting arrow

When designing your hunting arrow, we need to look at several things:

  • What animal or animals we are going to be hunting?This is a factor in choosing the weight of the arrow.
  • Is there a certain speed you wish to maintain?For some this may be 250 fps or 300 fps. This will be up to you, and maybe speed just may not matter to you.
  • What is your ideal total arrow weight?This will go with the fps, and the size of animal you’re hunting.
  • What is your ideal FOC?FOC is the balance point or center of mass of the arrow. FOC is and will help for penetration by controlling the amount of impact flex and allowing arrows to recover faster Other ways to improve penetration without having high FOC is running arrows stiffer in static spine, and using a system like the concept system by firenock.
  • What tip weight do you prefer?This will tie into the FOC of the arrow and total weight.
  • What style of broadhead do you want to use?The type and shape of broadheads also plays a role in what we need to build a good hunting arrow.
  • What type of fletchings are we going to use to control the arrow?This is what controls the drag on the back half of the arrow. Too much drag and we loose grouping at a distance. Not enough drag and we have the broad heads trying to control the shaft. This causes poor grouping at all distances.

Here is a list of twelve factories written by Dr. Ashby about designing a good
hunting arrow.

Dr. Ashby’s Twelve Penetration Factors of an Arrow

  1. Structural Integrity
    • The most important factor of arrow penetration is structural integrity. If any component of your arrow fails, then penetration either completely stops or is greatly reduced.
  2. Arrow Flight
    • If an arrow is not flying perfectly, then it’s wasting valuable energy that could have contributed to penetration. If an arrow impacts before it has achieved perfect flight, then energy is wasted that could have contributed to forward momentum and penetration. Perfect flight is crucial; you must achieve it no matter what the cost. Pay close attention to the other factors too though or you may find yourself shooting arrows that fly perfectly but can’t penetrate well at all.
  3. Arrow FOC (Front of Center)
    • Tests have shown that EFOC, defined as 19% – 30% front of center and Ultra EFOC, defined as over 30% front of center enhances penetration from 40% to 60+%.
  4. Broadhead Mechanical Advantage
    • Long narrow broadheads have an advantage over shorter wider heads. It takes less energy to push them through an animal. That is their mechanical advantage. This is second only to EFOC and Ultra EFOC as a penetration-enhancing factor.
  5. Shaft Diameter to Ferrule Diameter Ratio
    • You’ll lose up to 30% of your penetration potential if the shaft diameter is larger than the ferrule diameter where they meet. It’s best to be slightly smaller in diameter than the ferrule of the broadhead.
  6. Arrow Mass or Weight
    • Heavier arrows absorb more energy from the bow at the shot and heavier arrows carry their momentum better than lighter arrows, so heavier arrows penetrate better. Bow hunters should use the heaviest arrow that will deliver a trajectory they can live with.
  7. Broadhead Edge Finish
    • Broadhead edges that have been honed and stropped smooth have a 26% advantage over smooth filed edges and a 60% advantage over the coarse “serrated” Howard Hill edge.
  8. Shaft Profile
    • On all shots, tapered arrow shafts show an 8% penetration gain over parallel wall arrow shafts and a 15% gain over barrel tapered shafts.
  9. Broadhead/Arrow Silhouette
    • Smooth transitions and slick arrow finishes greatly enhance the penetration potential of your broadhead/arrow combination. Broadhead ferrules with bumps or any irregular surfaces impede penetration, especially in bone.
  10. Type of Edge Bevel
    • Only if no bone is encountered, then the type of edge bevel ranks 10th. If bone is hit, and more often than not it is, this factor jumps up toward the top of the list. If you can’t get through the bone, penetration stops. The powerful rotational force of single bevel broadheads splits bone. Single bevel broadheads regularly turn what would be a wound into a killing shot. Note: Your arrow must be of sufficient weight and strength to drive the broadhead through and withstand the forces involved in breaching the bone.
  11. Tip Design
    • In all testing where bone was encountered, the Tanto tip performed best. It resisted damage and skipped less than any other tip design.
  12. Arrow Mass 650 grains and Above
    • When soft tissue is hit, this factor is ranked last in importance, BUT if heavy bone is hit arrow mass will be near the top of the list. Heavy bone is almost impossible to breach unless you have 650 grains or better in mass arrow weight.

So now we have looked at an introduction what we want in our hunting arrow it’s
time to start choosing our arrows.

Coming Soon…

Part 1 will be choosing the spine and what to look for.
Part 2 why we want FOC
Part 3 will look at broadheads
Part 4 will be testing our arrows with ram tester.
Part 5 will be tuning the arrow dynamically.
Part 6 will be on tuning the bow.
When completed you will have a great hunting arrow
2017 EWN

   
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About Author

Eric, a bowhunter of 25 years, has hunted everything from whitetail deer and hogs to mouflon sheep and zebra. Eric is considered an expert by many on arrow and broadhead design and enjoys getting into the physics behind hunting. His papers on tuning, penetration, and arrow design has helped many others achieve maximum performance out of their equipment.

“There is more to bowhunting than just shot placement; you must design the right system for the animal you intend to hunt. “

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