Understanding Dynamic Arrow Spine Characteristics

By Paul Fender

Having nothing better to do, one day, I wanted to look at the vibrations that are created in an arrow upon release. I knew that I couldn’t really test or view what happens to an arrow during its entire flight. I realized though that I could test a bench top “simulation.” Using a digital storage oscilloscope (DSO), and an RPM sensor out of an old automotive electronic ignition, I was able to precisely time how long different arrows vibrated when I plucked on them and set them to vibrating. I knew the sensor would be sensitive to the steel of the arrow’s point.

A side note here. I realize that my little test is not real life. But I believe that it is reasonable to figure that the arrow’s behavior on the test bench would at least mimic real life and give us a good clue as to what is going on.

The pic “The Test Rig” shows my whole set up.

“Sensor” is the sensor I salvaged out of an old Honda distributor.

“Oscilloscope” is my Snap-On DSO. (I tell you this thing is way cool.)

And “Fixed Point” just shows that I simply clamped down one end of the test arrows.

After an evening of sorting through my wood arrows I was able to find two arrows that had the same static spine and same weight (within 10 grains) one parallel, one tapered. Both had the same point weight. I made sure to clamp each arrow so that they both had equal free lengths and same distance from the sensor. Making sure to pull each arrow down the same distance each time, all I had to do was release it and I was able to “see” the vibrations on the DSO and time them. I did this 10 times for each arrow and took an average.

“Parallel” is a snapshot taken from the test run with the parallel shaft and is an example of what the DSO was showing me.

Well folks, sure enough, there is a difference! The parallel shafts vibrated an average of .75 second LONGER than the tapered shafts! That was encouraging, so just for the heck of it I tested a few more different arrows but without bothering to match weight and spine. Naturally there started to be some overlap on some of the arrow’s results. However even without controlling for spine or total weight, as long as the arrows were correctly positioned and had the same point weight, it got even better with the tapered shafts vibrating for 1.25 second less time on average.

Not wanting to go too far afield though, here are the average vibration times from the “controlled” shafts.

Tapered – 6.1 seconds

Parallel – 6.8 seconds

“Taped Harmonics” is a sample of what I was seeing when testing the tapered shafts. This is where it gets interesting, so I highlighted the waveform in red. Notice how the amplitude, the signal strength, gets weaker and then stronger in ever diminishing waves until the vibrations are damped out. I believe that this is an important clue as to WHY tapered shafts recover from paradox faster.

One time …..at band camp….I learned that things can vibrate at resonant frequencies. A so called “standing wave” is created. The pic “Standing Wave” is an illustration of a cylinder resonating at different standing wave resonant frequencies.


Standing waves tend to be self-reinforcing and can persist for very long periods of time even without putting more energy into whatever is vibrating. I have a hypothesis, (which I doubt I could ever prove) that the unique vibration of a tapered shaft is caused by what is called “destructive interference.” The pic “Destructive Interference” illustrates the idea.


The arrow attempts to fall into a resonant frequency, but as the vibrations travel up and down the shaft, when they hit the beginning of the taper some of the vibration energy is reflected back against the incoming wave. Not only does the effect get greater and greater due to the taper, but the taper also helps make the reflection more and more out of phase with the incoming vibrations. The reflections are chaotic and create destructive interference. The transition from regular cylinder to tapered cone helps to actively damp outstanding wave vibrations.

So although tapered shafts DO recover from paradox faster than parallel shafts, there is what I would call the “Speed Problem.” Although the addition of fletching must have an effect on paradox recovery, if an arrow is leaving a bow at say 180 fps, can an arrow recover inside of 10 yards? 20 yards? With my test method I was seeing vibrations persist from 4 to 6 seconds! That could translate into a rather large distance with the velocities we’re working with. I’ll have to see if I can figure out a way to look into that.

Now we do have lots of people reporting observations of better penetration with tapered shafts. I’m perfectly willing to accept those observations as being accurate. But I’m just not sure it’s because of superior paradox recovery. Rather, at this point I would ascribe that to the tapered shafts allowing a finer state of tune. The taper shape imposed on wood, which is inherently variable, helps each shaft more nearly behave like its mates. The initial flex created upon release occurs at more nearly identical spots on the different shafts. Its rather poor resolution but you if you look closely at the pic “Tapered Flex” you can see the flex in the arrow taking place near the beginning of the taper on that shaft.

So, if we have a bunch of wood arrows that all behave more nearly the same we’re also getting more consistent results during tuning. Better tune leads to a better, cleaner, launch, so paradox or not, the arrow is still travelling more nearly straight and impacts the target (animal) squarely.

It was later suggested that I look at carbon arrows. After all everybody knows that carbon recovers faster. Fine, but where’s the proof?

OK, these results will surely upset the apple cart. I went ahead and used what I could find. I also included an aluminum arrow. Using the same methods that I used with the wood arrows, I got the following average vibration duration times.

Carbon GT 600 Ultralight – 8.1 seconds
Easton Carbon One 780 – 9.8 seconds
Aluminum Easton 1816 Platinum Plus – 11.25 seconds

These are the only explanations I can come up with for these results.

1) Since the carbons do damp faster than aluminum, and aluminum was THE shaft of choice when carbon shafts first appeared, it became accepted that carbon was better across the board, although that is not strictly true.

2) I need to test high dollar A/C/E’s and A/C/C’s. They may have led to the belief that carbons damp faster. Being 2 dissimilar materials bonded together I would bet that they do damp out vibrations faster.

It does make sense to me in that the super regular microscopic arrangement of the carbon fibers would tend to support the creation of harmonics and standing waves rather than damp them out. This effect would be even greater in aluminum shafts with the regularity of metallic crystals down to atomic scales. Wood, with its inherent irregularities and variability would tend to damp out vibrations rather quickly, regardless of parallel or tapered.

Perhaps a cross woven carbon shaft would damp well?

Now, as a “quantifiable” measure I know that I can shoot higher scores with carbon arrows. I’m becoming more and more convinced that it is consistency that makes tapered more accurate. We know how critical tuning is. So consider this, tuning is like running a specific set of experiments, If the shafts we’re tuning all behave more nearly the same the margin of error is smaller. We are able to achieve a finer state of tune. The error bars in our data acquired during tuning are smaller. Plus, once tuned, there is benefit in that the tapered all more nearly launch the same as each other as well.

 

Going Low Tech

By Paul Fender

Nico has flattered me by asking me to write a particular piece for the Ohlone blog. Naturally I jumped at the chance as, to be honest, flattery will get you everywhere with me.

There is a growing interest in shooting bows that are shot “off the shelf” or “off the hand,” where there is no shelf at all.  These are types of shooting that are often seen with Longbows, old Recurves, and Selfbows, or Primitive Bows. There are many reasons why somebody might want to head in this direction with their Archery. Some appreciate the simplicity of the equipment. Others may feel that it is more in line with their feelings about what Traditional Archery means to them. Regardless of why a person might want to go this route, I just want to say that going “Low Tech” is no reason to accept not being the best shooter you can be. Nico has asked me to write this so I can share some of the stuff I know, in order to assist folks in shooting their best, while doing so with some of the most challenging equipment a person could choose.

Some folks will tell us that in order to shoot “Traditional”, to shoot off the shelf or off the hand, we need to shoot in some sort of unorthodox, special, different kind of way. Nothing could be further from the truth. Whether hunting or target shooting, for the vast majority of people, they will get their best results from starting with good fundamentals firmly established in their shooting form. The place to start with those fundamentals is to be found in classic “T-Form” such as what Nico demonstrates in his introductory classes. Here is one of my favorite pictures of T-Form.

It dates from the 1800’s. Personally I think it’s ok to consider a style of shooting over 100 years old as being “Traditional.”

There are more advanced methods, such as NTS as taught by Woody here at Ohlone, as well as the KSL Shot Cycle, or the older BEST Method. There is a LOT to gained by the Traditional shooter examining and learning from these approaches. The important part here though is to realize that these approaches to shooting, although considered to be more advanced, or maybe reserved strictly for the target shooter, they are ALL based on that classic T-Form foundation.

I myself like the basic old 9 steps to the 10 Ring as shown here.

I like it I guess because it just keeps things simple. For me it’s like it’s right in keeping with the idea of shooting the simple equipment. When I visualize this sequence of pictures, despite the simplicity, I actually get a great deal out of it. Right there, there’s my T-Form. Plus, again, right there, there is my simple and easily manageable shot sequence. I can’t stress the importance of having a thoroughly ingrained shot sequence enough. It keeps your head in your shooting, and not off wandering about.

Another fundamental aspect of shooting is the grip. We all develop a certain grip style, and shape that we prefer. However, again, there are certain fundamentals that just aren’t going to change. Take a look at this graphic.

In the top row of images, that black oval represents where you want your hand to take the load created by drawing the bow. You want it just towards the thumb side of the “life line” in the palm of your hand. Now in the second row, you’ll want to try and pretty much fall in line with one of the first three images. I myself shoot a meld of the first and third images. Index and middle finger loosely completely around the bow grip, with the ring and little finger folded under. I picked up on this when I first took up Longbow, before bow and finger slings were ruled legal for Longbow competition here in California. The draped fingers keep the bow from jumping forward out my hand. The folded fingers help with proper elbow rotation. The two types of bows most commonly shot of the shelf or hand, Longbows and Selfbows, tend to run pretty low brace heights, so having your bow arm elbow rotated out becomes pretty important to avoiding string slap on the arm.

We’re all familiar with the grip shapes we see with most recurves. However, there is another type of grip out there that is fairly common in Longbows and Selfbows. I call it the “Broom Handle Grip.”

Here’s a picture of a Selfbow that I built. (This is the one that I took the World Record with at Yankton in 2014.)

See the black leather wrapped grip area? Yep, the grip on a Selfbow is just about like grabbing a broomstick. The same grip style is found on what are called “Hill style” Longbows, although they do have an arrow shelf. The Broom Handle grip does force a low wrist bow hand position. Funny thing though, even though I shoot this bow off the hand, I still grip it the same way I do with all my other bows, Recurve or Longbow. I guess if it ain’t broke, don’t fix it.

I’m going to throw in a little “trick” here for shooting the Broom Handle grip. Do a leather wrap on the grip area and install it yourself. With a little fooling around you’ll find a spot where you can tie off the finishing stitching knot so it provides a little “index” that you can feel under your index finger. That index will give you confirmation that you’re putting hand on the bow in the same place every time.

Having a properly tuned bow and arrow combo is of course fundamental to good shooting, regardless to what equipment style you’re using. Nico is running a good tuning guide on his site and it is available here:

https://ohlonearchery.com/new/wp-content/uploads/2015/05/Traditional-Archery-Tuning.pdf

There are a few things that can be added to the basics to be found there. For one thing, although we’re not shooting with an elevated rest and plunger, it wouldn’t hurt to also read through this tuning guide also found on Nico’s site:

https://ohlonearchery.com/new/wp-content/uploads/2015/05/Tuning-For-Tens.pdf  For example, when bare shaft tuning we can obtain finer tuning by moving back to longer and longer distances.

There are a couple of things that are often overlooked when bare shaft tuning. Don’t forget that your tuning decisions must be made based on the COMPARISON of the point of impact between bare fletched shafts. Don’t make decisions based solely on one configuration alone. Also, despite what some may say, bare shaft tuning is the “gold standard” even for wood arrows. It’s just that with wood you have to accept that you will be shooting larger groups than if you were shooting synthetics, carbon or aluminum. This is especially true when looking at the bare shaft groupings. So truly try and find and consider the positioning of the centers of the groups.

The first tuning guide points out that we need to create a clearly defined pressure point on the shelf for the arrow to sit on. I want to point out that we also need to create the same thing on the strike plate on the riser that the arrow rests against on its side. That pressure point needs to line up with the pressure point that we set up down on the shelf. It can be a thin strip of leather or section of a paper match underneath the strike plate.

That brings up something of a “one off” situation we might see. Often when we consider shooting off the shelf we may also be considering shooting a nice old “collectable” bow from the ‘60’s. Many of those bows do make real sweet shooters. Not real barn burners, but smooth draw with very low hand shock. Once in a while though we’ll run across one where the shelf and riser are cut totally flat, like this Benson Pearson model:

Although an “Old School” bow, this bow was actually never meant to be shot off the shelf, despite how it may initially appear to us.  Rather it was meant to have a stick on elevated rest like the Hoyt and Weather Rests you can get at Ohlone. But that doesn’t mean that we can’t shoot it off the shelf though. We just need to get a little creative and make sure to build up a high pressure point on the shelf and make sure that we have a corresponding clearly defined pressure point on the riser. We seriously need to do this with a flat shelf and riser bow like that Ben Pearson. When we release the arrow, the initial bending and flexing of the arrow may set up sometimes by the arrow pressing against the leading edge of the shelf and riser, other times it may be set up with the trailing edge. We just can’t count on it happening the same way twice in a row since we’re using a finger release. This is especially true if we’re shooting wood arrows. We need to make sure that the arrow has only one single place it can press against, time after time.

What about when we shoot off the hand though? That is another aspect of my own style of grip when shooting off the hand with a Broom Handle grip. It works out that my index finger works the same as an arrow shelf. It may not be a clearly defined hard little bump for the arrow to sit on. But it sure beats having the arrow attempt to pass over the whole stretch of skin, fat and muscle that make up the “web” that runs from your thumb to your index finger.

Now as we’re going along here, getting our equipment together, we eventually need to pick out which arrow we want to use. After all, getting the correct arrow is part of tuning, right? This will get somewhat convoluted, but if you bear with it, and just accept it for being what it is, it will kind of make sense. Going back to the Traditional Tuning Guide you’ll see an arrow selection chart. Covering aluminum and wood shafts. But what about carbon arrows? We can work with those too. Arrow spine, that is how much an arrow shaft bends, is measured as deflection in inches. There are 2 methods currently in use. There is the AMO method, which is based on setting an arrow shaft on 2 supports 26” apart, and then hanging a 2 pound weight on the middle of the shaft. You then measure how far the arrow bends in thousandths of an inch. This is an old method and is now used exclusively for wood arrows.  You can then divide the number 26 by that measured deflection and the result will give you an approximation of that shaft’s spine weight in pounds. That will roughly match what bow draw weight that shaft should work with.

There is now also the newer ASTM method of measurement. That is based on the same idea, but using different specs. Using 2 supports, 28” apart you hang a weight that weighs 1.94” in the middle of the shaft. That deflection is again measured in thousandths of an inch. Why the 2 different methods? Everybody has a theory, but honestly, nobody knows for sure. For real. It is what it is. The ASTM method is for use with the synthetics, carbons and aluminum. So, here is a quick chart showing the arrow sizes from the Tuning Guide, and their corresponding ASTM deflections.

Size                 ASTM Deflection

1616                1.079”

1716                0.880”

1816                0.756”

1916                0.623”

2016                0.531”

2018                0.464”

2020                Discontinued

2117                0.400”

2216                0.375”

2219                0.337”

Knowing that carbon arrows are measured just like aluminum arrows, and having the above information, and using the Tuning Guide, we can make an initial shaft selection that will be tunable in either aluminum or carbon shafts. For specs on a particular make and model of carbon shaft we can go to the manufacturer’s website and find the ASTM deflection numbers.

Now let’s say one of you is truly demented, like me, and wants to take a stab at shooting wood arrows. There’s the chart in the Tuning Guide of course. But what if you’ve been shooting a synthetic and already have a well tuned good shooting set up.? It is possible to convert an ASTM spec shaft to a usable wood shaft spine weight group. We can state the math simply enough using the conversion factor of 0.825. It’s just a dimensionless “fudge factor” that will generate a result close enough to direct us to a tunable arrow.

ASTM X 0.825 = AMO

Conversely

AMO / 0.825 = ASTM

Once we have derived an AMO deflection number from the conversion we can get the wood arrow spine.

26 / AMO = Spine in #’s

We can finish this off with a real world example. So, you have a longbow, shooting off the shelf, and you’re using a carbon arrow with an ASTM deflection of 0.600, and it is well tuned and shoots well. Doing the math:

0.500 X .825 = 0.495

26 / .495 = 52#

With that info, you would be looking to buy a batch of wood shafts sold in the 50#-55# spine group. That would give you a tunable shaft to begin working with.

There are other variables to consider when making shaft selections. There are a few rules of thumb that kind of work to go with those variables. For every inch longer that the shaft is, consider selecting as if you needed a shaft for a bow that has a 5# lower draw weight. The Tuning Guide chart is based on using a 125 grain point weight. For every 25 grains heavier point that you want to go, consider selecting a shaft that would go with a bow that is 5# heavier draw weight.

How close the arrow shelf is cut in towards center naturally has a direct impact on tuning and shaft selection. There is no real rule of thumb here. Both brace height and the quality of our release are players here. There is one thing I can tell you. If you’ve really lost your mind and want to shoot off the hand, absolutely no shelf, no cut in towards center, you will need to select a shaft that is for a bow with a lower draw weight than what your bow actually measures. At least 5#, possibly 10#.

Of course, everybody eventually asks the question, “OK. So how do I actually AIM the stupid thing?!?!?!” Nico has already taken a stab at answering this question with this blog post of his:  https://ohlonearchery.com/new/wp-content/uploads/2015/05/Aiming.pdf Look through that, try a few, you’ll find something that yields the best results for you personally. Aiming methods are going to basically run independently of whether we’re using an elevated rest and a plunger, or if we’re shooting off the shelf or hand.

I do want to add this one caveat concerning “Instinctive” aiming. I myself am a gap shooter. But I did give instinctive a go at one point. I also wrote a piece on it, which can be read here: https://ohlonearchery.com/new/category/paul-fender/  From my own observations and experiences I can say that it does work. But it really isn’t for everybody. It really kind of depends upon how your head is wired, whether or not you’ll really be able to tap into it and get good results from it. Also for those who believe that they can make it work, be prepared to put in years of work before you really hit your stride with it. So, all I’m saying is that it is doable, but it is a tough row to hoe.

I think that at this point we’re finally getting past basic and fundamental considerations, and more into what I might call “nuances.” Just little bits of advice, some of which go with shooting off the shelf or hand, and some which also go with other equipment configurations.

This is one of my favorites. Use two nock sets on your string. One above the arrow nock like normal, and another to go below the arrow nock. Use a “tie-on” nock set made by knotting braided string or serving material onto the bow string. Use the tie-on because it is soft and conformable. You don’t have to agonize over how much spacing to provide between the arrow nock and the nock sets. Also, the tie-on nock set won’t chew up your tab or glove like a brass crimp on type does when used for a bottom nock set. You’re probably wondering why 2 nock sets. Depending upon nock fit, and your release, without a lower nock set the arrow nock can slide down the string on release. We call it “nock slide.” This is most prevalent with shooting 3 fingers under the arrow, as opposed to split finger, index above the arrow, middle and ring finger under the arrow. That nock slide effect leads to porpoising arrow flight, and random unexplained high/low hits. It can even be so bad that the arrow slides down far enough that the back end of the arrow hits the shelf hard enough that the back end wildly bounces back up into the air.

Maybe not the best of pictures but I was able capture these 2 stills out of a video showing nock slide actually happening.

Here is the arrow position on the string, shooter is at anchor, just before release.

And here is arrow position on the string, just milliseconds after release.

Somewhat difficult to see, but the arrow nock has slid down the string, somewhere between 1/8” and 1/4”. Even if a person is running a nock height high enough that the nock slide doesn’t directly affect tuning, it is enough to affect the arrow’s point of impact down range at the target. Keep in mind that the longer the distance, the greater difference will be. Also, it would be a mistake to count on the nock sliding down the string the exact same amount each and every time.

It is a matter of personal preference, but I would have to recommend shooting with the 3 under release, rather than split finger. For shooting without a sight, it will make any aiming method you chose, even instinctive, work out better, more accurate. Also, it significantly reduces the amount of spurious input that our string fingers can accidentally impart to the nock end of the arrow. I have seen people shooting split finger who had their fingers grabbing at and pressing on the arrow nock so hard that the arrow was actually bending by the time they hit anchor. This leads to some really funky, erratic arrow flight. There is really only time that shooting split finger might be a consideration. The International Field Archery Association (IFAA) mandates shooting split finger for competing in their Longbow class. For most of us this would be a consideration only when the United States hosts the IFAA World Field Championships. That happens about once every 6 years.

Fletching is definitely something that requires some thought if we’re going to shoot off the shelf or off the hand. It is certainly possible to use synthetic vanes. However, achieving a fine enough state of tune and a fletching orientation that will allow for good arrow flight right out of the bow is very difficult. Whether shooting wood, or synthetic shafts, I STRONGLY recommend using feather fletching. Ideally the arrow is launched with zero fletching interference with the shelf or riser. But with a finger release, sometimes Doo-Doo happens. We really do want an arrow that is the most forgiving of shooter error, and feather fletching gives us exactly that.

Some folks have opinions about whether one should use Right Wing or Left Wing feathers. The truth is that an arrow does not begin to spin until it is already several yards down range. If the arrow is leaving with good fletching clearance, it really does not matter if we’re shooting off the shelf. If we’re shooting off the hand there might be cause to select one over the other though. When using a very long fletch, and due to the feather being slightly “wrapped” around the shaft helically, the leading edge of the fletching may wind up being pointed down into the bow hand. When shooting off the hand, you only have a very narrow window in which to achieve a good state of tune. If you find that you just can’t seem to get the leading edge of the fletch to stop digging into your bow hand you could try switching which type of fletch you use.

Just in case you wind up having both types laying around and you accidentally get them mixed up, here’s a picture showing how to quickly tell them apart.

Even if we’re shooting a configuration that is forgiving enough that any one arrow doesn’t matter, you do not want to mix both Right and Left Wing on the same arrow. I would even go so far as to say don’t have mixed fletching within the same batch of arrows.

We can also play with fetching orientation. “Standard” orientation calls for shooting with the “cock” feather (usually the one odd colored feather) pointing out and away from the riser. Again, a good state of tune means that it actually shouldn’t matter. The shelves on some bows are really wide though. Using the standard orientation can lead to having to run a very high nock point setting and/or having the lower “hen” feather run into the shelf. For shooting off the shelf I recommend tuning to and shooting with the cock feather pointing in towards the riser. With good tune the cock feather won’t hit the riser because of the flexing of the arrow established upon release, and the hen feather will be to the outside of even the widest shelf. This helps us achieve a very good state of tune while running a low nock point. Having a low nock point helps us achieve greater arrow “cast.” (“Cast” refers to how far a bow will launch an arrow, and is important when shooting long distance competition such as what is seen in a Field round.) When it comes to shooting off the hand though, since there is no cut towards center, you might as well revert back to standard orientation. You’ll never be able to get the cock feather to make its way around the riser. The bow is going to be just too wide at the grip area.

Fletching length is also a hotly debated topic. Really though, there is no need for “debate,” per se. Rather just put some thought into what you’re trying to accomplish. Short fletch is good for outdoor competition. The lower drag improves cast. Longer fletch is good for Indoor competition in that cast is not a consideration and the higher drag improves forgiveness. It may also give you a better sight picture and point of aim to help improve your precision and accuracy. Those are big considerations for Indoor competition. If you’re shooting off the hand, again long is good, pretty much no matter what type of competition you’re shooting. You’ll gain some forgiveness.  Off the hand is already tough enough as it is.

I have some guidelines I do generally follow. If hunting and using broadheads, 5” long isn’t necessary, 3” is certainly shootable. So, I settle for 4”. Since a broadhead will want to try and steer an arrow from the front end, I want some fletch there to fight that and offer forgiveness, while not costing me too much down range Kinetic Energy being lost to drag. If I’m shooting wood arrows, for competition, I never shoot anything shorter than 3”. I found that 2” was just too short to help offset the inherent variability in wood arrows. (No matter how much you devote to culling, sorting, matching, and tuning your wood arrows, there is still some degree of variability.) For Outdoor competitions, both 3D and Field, I usually shoot 3” fletch, and certainly never longer than 4”. For Indoor competition, I have played with everything from 3” to 5”. It really just comes down to what you can tune and shoot to the highest degree of precision. If you’re just starting out, go with long fletch on your first Indoor shoots.

An aside I will throw in here, is that there is no one arrow that will do it all, and do it well. If you try for that, you just wind up with one arrow configuration that is a huge compromise, and does none of them well. I firmly believe in using the proper tool for the job at hand.

Since we’ve been talking about fletching interference I want to share a method I use for detecting it and eliminating it. When shooting off the shelf, fletching interference can become a real big deal, much more so than when using an elevated rest. I call my method the “Lipstick Method.” Get yourself some cheap red lipstick. (My wife Annette was NOT happy the first time I tried this and used her expensive lipstick. It really messes it up.) Pick one arrow and smear the  lipstick along the edges of your fletching. Then go ahead and shoot that arrow. It will leave distinct red smears on the riser and shelf where the fletch is hitting. I prefer the Lipstick Method because the marks left behind are easy to see and interpret. It is kind of messy, but the lipstick wipes right off with a couple of passes of a cloth rag. It even comes out of feather fletching with no damage to the fletching. So, given the lipstick marks we can decide if we want to alter the orientation of the arrow nock to the fletching in order to help the fletching get around the riser. You really don’t want to bring in this bit of fine tuning until somewhat later in the process. Trying it right off the bat as we begin bare shaft tuning would be pointless as we’re pretty much guaranteed we’re going to be getting some fletch interference in the beginning.

There is a consideration that goes with shooting off the hand in particular. What about using a protective bow hand glove? I prefer shooting any bow without a bow hand glove. The less between me and the bow the better. Running with no glove helps me ensure that my hand is going into the bow the same way every time. But when I first started shooting off the hand, no matter what I did, the arrow fletching was tearing up my bow hand. So, I broke down and got some cheap leather weight lifter gloves, and used the left one as a bow hand glove. (They only cost $8, so no big loss.) I wound wearing a hole in the glove at the index finger, laid down a leather patch, and then even wore through that. During this I was finally able to figure out that it was a matter of proper arrow selection and tuning. As I mentioned earlier, we have a much narrower window of acceptable state of tune when shooting off the hand. I was ultimately able to ditch the glove. But I will tell you, shooting off the hand was almost like learning how to tune all over again. Anyway, is a bow hand glove “required” for shooting off the hand? Not at all. But if you’re just getting into trying it out, you might want to get something. And no, you don’t need to spend big $ on a specialty bow hand glove. Any nice, light, thin leather glove will do, even if it’s a full glove and you chop the finger ends off it.

Although it’s not just for shooting off the shelf, I do recommend shooting with a finger tab rather than a glove for your string hand. Gloves are more convenient, but most shooters come to find that they get a better release with a tab. I think it’s because a tab promotes getting your fingers to behave more like a single “flipper” rather than individuals able to each do their own little thing. I started out with a glove. But I wore them out rather quickly and was always spending more and more on better quality gloves. This eventually got to be rather pricey. The last glove I bought cost $80, and it STILL wore out in less than a year. Now that I shoot a tab, I’ve found that they last a lot longer. I also make my own. I now get a better release, cost is not a big deal, and I always have a spare or two with me, just in case I lose my tab.

At this point I think I’m going to finish this off. I make no pretense that this is everything a person needs to know in order to be successful at shooting off the shelf or hand. Rather it is a just a look at some of the things I have learned and maybe they can help others achieve good results while not spending so much time learning stuff the hard way.

Arrow Velocity at Different Yardages

By Paul Fender

For some time now I have been wanting to get actual chronograph readings on arrow velocity at different yardages. I knew that the smart thing to do would be to build some sort of barricade in front of the chronograph so I didn’t accidentally shoot it and blow it up once I got out at some decent distances. After all, Doo-Doo happens, right?

I finally came up with a quick and easy way to cobble together a barricade that would enable me shoot across my chronograph, and that would effectively protect it while not utterly destroying any errant arrows. Good thing I did this too. Sure enough, I shot the barricade once. Oops.

What follows are the velocities I measured from 2 yards out to 35 yards. That was the longest distance I could get in my back yard while still having room for the chronograph and the barricade in front of the target butt.

Yards                                      Velocity in Feet per Second (fps)

2                                              204

10                                            196

15                                            188

20                                            181

25                                            174

30                                            170

35                                            167

Right off I noticed something that at first seemed odd. The first, closer distances measured showed larger drops in velocity than what was measured at longer distances. I then realized that this actually just makes sense. Drag is a major player in an arrow’s trajectory and how its velocity changes over time. The force that drag exerts to counteract forward motion is proportional to forward velocity. That is, the faster the arrow goes, the greater the force that drag exerts against the arrow. So, initial deceleration will be greater than the deceleration later in the arrow’s flight. This is of course a big part of why an arrow doesn’t follow a “true” parabolic ballistic trajectory.

Once I had that information I then realized that I could take things a step further and look into something else that I had been wondering about. I could figure out how fast the fletching was making my arrow spin at a particular yardage.

I built a “trap” out of a cardboard box and two sheets of paper. I opened up the box and taped the sheets of paper across the open ends. This put the 2 sheets of paper 18.5 inches apart. I then smeared red lipstick onto one fletch of one of the arrows that I had used for the velocity measurements. I just arbitrarily decided to figure out rate of rotation at 20 yards. So, standing 20 yards from my “trap”, I shot the lipsticked arrow through it.  This left clearly defined marks on both sheets of paper. Using a protractor, I then was able to measure that in the time it took for the arrow to pass through the sheets of paper, it had rotated 85 degrees.

I’ll save us all from having to trudge back through the math, but using the velocity originally measured at 20 yards, and knowing that the arrow spun through 85 degrees as it traveled 18.5 inches, I was able to calculate that the arrow was spinning at a rate of approximately 1660 revolutions per minute. That figure is of course rounded off. After all there is no point in trying to maintain some semblance of a precision of measurement that simply does not exist.

Of course, we’re now left with the question, “But what does all this really mean?” To be perfectly honest, not much. There is no real “conclusion” to be drawn from this. None of it is either “Good” or “Bad.” As they say, “It is what it is.” I just found it rather amusing to be able to finally answer a couple of questions that had been bothering me for a while.

Paul Fender

Paul Fender (a.k.a. “Coach Biff”), World Champion

My name is Paul Fender and I have been shooting Traditional Longbow and Recurve for about 15 years now. During that time, I have taken a several State, National, and International level wins. I have set a few records as well, including an International Field Archery Association World Record.

Although not a certified coach I have been lucky enough to have learned from some of the best here in the Bay area. I have worked to introduce new people to Archery, and to get those who aren’t so new back on track when they need it.

Whether a person is new or if they have already been shooting for some time I focus on grounding oneself in the basics, such as “9 Steps to the 10 Ring.” However my strengths have always been in the technical and psychological aspects of Archery. I believe that once an Archer gets to a certain point they can “level up” by beginning to pay attention to the details, both with their equipment, and within themselves.

In that spirit, I would like to offer here some excellent guides to bow tuning for those who wish to begin learning about tuning. I would recommend reading the one on Bow Tuning by O.L. Adcock first.

I live in Lake Co. California, but for those who want to bump up their game, contact can be made through Nico here at Ohlone Archery.

A Perspective on Instinctive Aiming

By Paul Fender

For those new to archery the term “Instinctive” describes both a general way of not precisely or consciously aiming and a specific style of archery developed and written about most notably by G. Fred Asbell.

It is briefly described in a document attached to my 2015 post, “Aiming Without a Sight”:

https://ohlonearchery.com/new/wp-content/uploads/2015/05/Aiming.pdf

World Champion Paul Fender goes into greater depth about it in this new post:

A Perspective on Instinctive Aiming by Paul Fender

Over the years I have accumulated personally witnessed evidence that what is commonly called “instinctive shooting” just doesn’t work worth a darn. However, at the CA State Broadhead Tournament I got to witness evidence that it does work. I, a confirmed gap shooter (reference to this also in my above mentioned post), took third to two confirmed instinctive shooters. Oh, the horror!

I have always had a hard time with the idea of instinctive shooting. We’re told “It’s just like throwing a baseball.” A moments reflection though and we realize that that can’t possibly deliver the accuracy necessary for either hunting or target shooting. Sometimes it’s called “proprioception”, the unconscious perception of the relative position of our various body parts. Think about that for a minute. I don’t know it for a fact but I find it doubtful that this sense of proprioception is so precise that it can drive the difference in elevation of the bow arm to accommodate for a 25 yard shot versus a 15 yard shot. But I have seen instinctive shooters do just that. Then of course there is the argument that there is no such thing as instinctive shooting as humans are not born with any instinct for shooting a bow and arrow. It is a learned behavior.

I have run across apocryphal (accounts of uncertain validity) stories of informal studies of instinctive shooting. In these studies, the performance of shooters who consciously aim is compared to instinctive shooters. The most common format is to have the shooters shoot at a “target” like a laser dot projected onto a wall in a totally dark room. In some of these “studies” the instinctive shooters perform best, in others the aimers do best, and in yet others there is no measurable difference in performance. So even if we do accept these stories as being valid, it’s still a wash. However, let’s just keep these stories in the back of our mind for a bit, OK?

Some time ago I read in the 5/2010 issue of Scientific American an article titled “Uncanny Sight in the Blind” by Beatrice de Gelder. She is a professor and the director of the Cognitive and Affective Neuroscience Laboratory at Tilburg University, Netherlands. Turns out that people who have gone blind due to injury to the visual cortex in the brain, yet whose eyes remain basically healthy have a “sense” termed “blind sight”.

People who have demonstrated blind sight are able to distinguish colors, shapes, and even emotions portrayed on other people’s faces, even though they are not conscious of having seen anything! One particularly striking case is that of a blind man who was able to successfully navigate an obstacle strewn hallway. Here is a link to a video of him accomplishing this:

What I found to be important and what has lead me down this long and tortuous path is that upon questioning, the blind man was not consciously aware of having perceived anything or having made any maneuvers to avoid the obstacles!

So, by accepting the stories about the instinctive shooting studies and their equivocal results, (yes I’m going out on a limb here) and combining them with the concept of blind sight I have arrived at a theory of instinctive shooting. For one thing, yes it can work. In order for it to work though, the arrow, or the bow’s shelf, or sight window, or other reference MUST be visible to the eye. These references are actually processed. They are used to drive what the shooter does with his body, much like the blind man in the hallway. However, the instinctive shooter has managed to train himself into a sort of blind sight condition in which this processing is no longer happening consciously. This processing is occurring in the more “primitive” areas of the brain. An oversimplified view of brain functions, but think of it as if this processing is occurring in the “reptile brain” we all have. Perhaps the term “instinctive” isn’t quite such a misnomer after all?