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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.

NTS Step 1 – Stance

By Level 3 NTS Coach Woody Walters

This month, we’re going to dig into Step #1: Stance.

The stance is the foundation of the shot.  Your foundation must be stable and consistent if you want to hit your target with any regularity and precision, therefore, your bio mechanical efficiency starts right here.

The NTS prescribes an open stance rather than the square or closed stance taught to most beginners.  This means that if we draw a line from where you are shooting to the target, rather than placing your feet parallel to that line, the toes of the front foot are slightly behind the line while the rear foot’s toes are right on it.

This is a more stable position, especially when shooting on uneven ground or in wind.  The feet should be about shoulder width apart with your weight evenly distributed on both feet.  Most archers don’t realize that they shoot with their weight planted on their heels as if they are standing at attention.  If you’ve ever played another sport, it would be unfathomable to consider yourself as standing in an athletic position with your weight on your heels.  The same goes for archery: you should have 60-70% of your weight on the balls of the feet.  Just like if you were about to shoot a free-throw in basketball, this places your center of gravity approximately between the insteps of your feet.  Placing your weight on your heels will cause you to sway back and forth during the aiming process.  How are you supposed to hit the bullseye when your sight pin or arrow tip is swaying back and forth with you?

In addition to foot position, Stance addressees posture.  You may have noticed that high performing archers do not stand straight up with the curved spine/chest forward stance you see in a person standing at attention. Instead we stand with a flat spine and the chest turned down slightly.

This position is acquired by tilting your hips back slightly. Tighten your lower abdomen and squeeze your butt muscles.  You’ll notice your hips tilt back causing your lower spine to flatten out as shown in the diagram above. This position lowers your center of gravity, further improving balance, and reduces the load on lower back muscles, reducing soreness or potential for injury.  This posture also has the benefit of making it easier to generate power in your draw/transfer/hold.  You want to shoot the highest draw weight possible to reduce the potential for external factors to impact the flight of your arrow.  You don’t do that by simply getting stronger – proper posture is a major factor.

This chest down stance is different than leaning forward during the shot.  Again, refer to the pictures above.  You’ll notice the archer is not leaning forward from the hips.  Her spine is on a vertical line top to bottom.  I cannot discourage you enough from leaning forward during your shot.  A lot of new archers make this mistake and if you think you are not doing it, go grab your bow and stand in front of a mirror.  You may have a slight lean that you are not aware of.  This posture cancels the benefits of proper spine shape and places a lot of unnecessary stress on your lower back muscles.  You are not generating any more power or balance while leaning forward, so let’s get rid of it!

Remember, trying something new is always difficult.  You are going to get confused, feel sore in new places, and have to change your aiming point or sight alignment.  These are all good signs because they mean that you are challenging yourself mentally and physically.  If you get lost or have questions, feel free to send me questions or talk to Nico and myself at the range.  We love to help.  Healthy and accurate archers are happy archers!

15 Screws To Keep Tight On Your ILF Bow!

Congratulations, you just bought your first ILF bow! Maybe you chose an ILF bow for it’s ease of break down and set up; maybe you wanted a specific color; maybe a metal “techie” look is more appealing to you than a wood bow; maybe you like the versatility of limb choices; maybe you like the mass weight compared to a wood bow (or maybe you got the best of both worlds and bought an ILF wood riser). Whatever your reason, you now need to know one thing about your ILF bow: there are lots of little screws and nuts & bolts that can and will rattle loose with the shock of shooting your bow. More important – many of those little screws, nuts & bolts and parts & pieces to which they are attached are hard to replace – some are irreplaceable! If you are not “mechanically inclined” this may be a problem for you. But hey, you built that IKEA desk didn’t you? So don’t sweat it; read on and look closely at the pictures!

The bow example is an SF Archery Axiom Plus Light and a set of SF Archery Axiom Plus Recurve limbs. Other bow models may have more or fewer screws, nuts, & bolts than this one.

The focus of this post is for newbie SAFETY and keeping your riser in one piece. If you want to know exactly what these screws, nuts & bolts do, and why, read this “manual” for the SF Archery riser: SF Archery Axiom Manual. Your bow can become very unsafe if most of these screws, nuts & bolts come loose – please get help from your pro shop if you are reading this too late. Also, find your nearest local SMALL hardware store – they will be more helpful to you than a big impersonal store in finding that one little .08 cent screw that means the difference between you being able to shoot your new bow or not. Otherwise, read and learn.

Clicker Blade Screw – Remove It

This little screw allows you to mount a blade style “clicker” onto your bow. You probably don’t know what that is yet. Forget about it. If you decide to get a clicker of any quality later, it will come with a screw. But because this one is there for no good reason, it will fall out one day and freak you out. Someone will see it fall off if you don’t, and you’ll be, like, Oh No! A screw fell off my bow! Is it important?!! Remove it and throw it away. I remove these from the bows I sell, yet I frequently find them on the floor of my shop – what does that tell you?!

Grip Screws – periodically check and tighten if necessary

We’re going to start easy and build up to more scary things as your confidence builds.

These two little screws mount your bow grip to the bow. Your bow grip is your most important interface with your bow – equal to the string. If the grip screws become loose the bow grip will shift under the weight of the draw – it could cause erratic shots. It will almost certainly cause weird creaking noises that will drive you nuts. There should be one on each side of the grip. On the example bow, there are Phillip’s Head screws – on some bows, they are small hex head screws.

Limb Bolts – periodically check and tighten if necessary

Your ILF Bow is designed to allow you to increase or decrease the draw weight by a minor degree, maybe 1 – 1.5 LBS in either direction depending on draw length. This is accomplished by loosening a lock screw (2nd photo, the one on the back of the riser), then turning the shiny flat bolt on the front of the riser either clockwise to increase draw weight, or counter-clockwise to decrease draw weight. If you are a newbie and/or not mechanically inclined, FORGET THIS – it’s complicated and potentially dangerous to mess with this. However it is very important to periodically check both of these bolts for tightness and tighten them down if they are loose. Notice the nice little pack of hex head wrenches that came with this bow in the 3rd photo. Also notice the two “multi tool” sets in the photo – these do not come with the bow, but you need them. One metric and one SAE (American). Many, many risers and bow accessories have half metric and half SAE nuts & bolts holding them together! In the SF Archery riser featured here, the 5mm hex head wrench in the 1st photo that is supposed to fit that bolt doesn’t! It’s too small and any moderate force would result in you stripping the bolt! Take charge, get yourself two multi tools.

Block Bolt – periodically check and tighten as necessary

This limb flange “block” is 50% of what holds that limb safely and securely in place after you magically snap that limb into place. The other 50% is that rod/bolt under the shiny disk bolt that you checked and/or tightened in the previous step. I’m focusing on safety here. If that sucker works loose and you don’t notice, very bad things can happen. Check it. Tighten if necessary.

Limb/Riser Adjustment screws – frequently check and tighten as necessary

If you look closely at the block bolt in the previous photo, you will notice two screws on either side of it. These screws allow you to shift that block left or right to best “align” the limbs in the riser. For some reason, these rattle loose more than any other screw/bolt on the bow. CHECK THEM MORE THAN PERIODICALLY. I’ve also found them hard to replace for a couple of bows – CHECK THEM AND DON’T LOSE THEM! There is one on each side of the top and bottom limb bolt pockets for a total of at least 4 (I came a cross an ILF Traditional riser that had TWO on each side for a total of 8 screws – CHECK THEM!).

The ILF Limbs Themselves – frequently check and tighten as necessary

OK, here’s the one that catches everyone off guard. That slick little magic disk that slides into the limb pocket block is made up of many parts that can and will rattle loose! There is a screw or hex head bolt that holds everything in place. There is a pin that “floats” with pressure from a small spring that allows you to snap that limb into place, and most importantly, pull it back out without a lot of effort and no tools! There is sometimes a little collar that the screw nestles into. If you lose any of these parts you will most likely need to buy a whole new set of limbs. My supplier scrounged up a set for me ONCE for a customer – we made a set of Frankenlimbs that worked.

Now here’s the part where the moderate to severely mechanically inclined can stop screaming at me. Get yourself some “Threadlocker” also known as “Locktight.” It’s a little tube of gel that you can apply to the threads of most of the screws, nuts & bolts I’ve identified. It will “lock” them in place. That can be good and bad. I can see no reason not to apply it to the limb flange screws – can’t imagine why you would ever WANT to take those apart. But you may at some point WANT to adjust all the other screws I’ve shown you. Putting thread locker on those other screws may make it difficult for you to loosen them when you want, so defer to checking and tightening periodically (or frequently as noted).

Sorry to be a buzz kill after you felt so good about buying that new bow – but I want you to enjoy it forever. With great bow comes great responsibility 🙂

Using the National Training System Steps of Shooting to Become a Better Archer

By Level 3 NTS Coach Woody Walters

Developed by the Head Coach of USA Archery, Kisik Lee, the NTS is a philosophy for how to shoot archery in a biomechanically efficient manner which minimizes the potential for injury and maximizes the potential for accuracy and peak performance.  This is the philosophy and technique used by America’s Olympic archers and it is now mirrored by high level archers all over the world due to the rapid ascension of athletes coached by Lee in the sport.

Despite the simple nature of the sport (grab bow, load arrow, pull back, aim, release arrow) there are a lot of ways to shoot arrows and they are not all created equally.  If you are moving through the steps of shooting out of sequence or using the wrong muscles to generate and hold tension, you will ultimately create a point of failure in your shot process.  You will shoot high scores at 10 yards, but fail to score well at 20 or beyond.  You will wonder why your shoulders or biceps hurt every time you shoot.  You will wonder why you still slap your arm with the string after years of shooting.  You will potentially struggle to shoot well or consistently in competition.

The NTS can help solve all of these problems and more whether you want to become an Olympic archer or simply have fun a couple times per week.  The best part is these techniques apply to recurve and compound shooters alike with minimal variation.

Let’s take a look at the steps:

  1. Stance
  2. Nock
  3. Hook and Grip
  4. Set
  5. Set-up
  6. Draw to Load
  7. Anchor
  8. Transfer to Hold
  9. Expand and Aim
  10. Release and Follow-through
  11. Feedback

Each month I will publish a blog post focused on one step within the system and how you can utilize it to your advantage.  You do not have to adopt every aspect of the NTS to become a good archer, but every good archer does use these steps to their advantage.  If you overlook the importance of any one of these steps, you will limit your potential as an archer.

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.