This article is a part of series answering archery questions. Today I’ll be answering the question, “can the draw length on a bow be adjusted?”
Almost all compound bows have an adjustable draw length. The range of draw length adjustment is different for every bow. Some have a very large draw length range of 15-20 inches, while other compound bows can only be adjusted 3-5 inches.
For instance, on the left The Hoyt Powermax has two options available. One cam for 24-25″ draw length and another cam is for 25.5-30″ draw length. However, the Diamond Edge below has an adjustable draw length of 15-30.”
Let’s take a look at what draw length is and why compound bows can have different draw length adjustments.
Compound Bow Draw Length
What is Draw Length?
Draw length is the set distance a compound bowstring can be drawn which is specific to every archer. This distance is based on the length of your arms and will be the fixed distance between the middle of your bow riser and the nock of the arrow when it is drawn.
Why Is Draw Length Set on a Compound Bow?
It’s necessary to set the draw length on a compound bow because of its use of cams. The majority of cams are oval, and when the bowstring is drawn, the cam turns over creating what is known as “let off.”
Let off allows the archer to hold the bow in full draw at a fraction of the actual draw weight. For instance, if a bow has a draw weight of 60 pounds with 50% let off, the bow can be held in full draw with only 30 pounds of force.
Let off is a major benefit of the compound because you can hold in full draw for longer which can help with aiming. This is especially useful in bowhunting.
Since the cam has to rotate a certain amount to provide this let off, the draw length on compound bows is set. This is known as the “draw wall.” This means if you set the draw length for 28-inches, it will not work for someone with a 26-inch draw length. That person would need to adjust the draw length, which will allow the cam to make its full rotation at 26 inches.
How To Find Your Specific Draw Length
Finding your overall draw length is relatively easy. You need to measure your arm span, which is the distance of your arms stretched out horizontally. This is easiest if you have someone to help you. Have them take a tape measure while you extend your arms out. They will then measure the distance between the tips of each middle finger. Once you have this number, you will divide it by 2.5, and this is your approximate draw length.
If you don’t have someone to help you, measuring can be a little trickier. One way I have used is to grab a pencil and stand against a wall. It’s best to utilize the corner of the room so you can extend one fingertip all the way to the corner. One this is done you can use that arm to mark your other fingertip with the pencil.
A third way is to pull out your tape measure on the ground. Then lay down and extend your arms. You will need to work to get one hand’s middle fingertip lined up with the end of the tape measure. You can then check the number of the opposite fingertip to get your starting number. Again, divide the measurement by 2.5, and you’ve got a rough estimate of your draw length.
Once you have your rough draw length, the next step is to adjust your bow to that length. It’s a rough estimate because once you begin shooting the bow, you may find the draw length slightly too short or too long. If you measured correctly, the number should be within a half inch of your correct draw length.
The final draw length can vary, however, based on your anchor point which is unique to every archer. You may find that a half inch shorter or longer on the draw length is best for your specific anchor point.
How To Tell If Your Draw Length Is Too Long
It is relatively easy to tell if your draw length is too long. Since the bow will have a set draw length, when it is in full draw it will have a hard stop. In other words, you can’t draw any further.
If you draw the bow back to your anchor point and don’t feel the hard stop, you should know it. Every compound bow has different designs for what is known as the “the valley.” This is set distance in the draw cycle before the hard stop where the draw weight is reduced slightly.
This should not interfere with finding out if your draw length is too long. You should be able to draw to your anchor point and no further. If you don’t hit that hard stop at your anchor point, you need to shorten your draw length.
How To Tell If Your Draw Length Is Too Short.
When you measure your draw length and adjust the bow accordingly, the distance should not be too far off. It’s more common for archers to have a draw length that is a little too short rather than a little too long.
The reason is that you can compensate for too short a draw length. Many archers cramp up, bend their elbow which brings the bow closer to the body or leans their head forward to meet the bowstring.
All of these things indicate the draw length is too short. It’s vital to your accuracy that you develop proper form and adjust the bow to meet your exact needed draw length. You can read this article on improving your accuracy by different form training methods.
That article mentions filming yourself shooting which can be a good way to tell if your draw length is too short. Watch yourself shooting to see if you are relaxed and extended which your chest opened up when you are in full draw. If you see yourself leaning your head forward to meet the bowstring or bending your bow arm to bring the bow closer to you, your draw length needs to be adjusted.
Adjusting Draw Length On Compound Bows
I could specifically show you how to adjust the draw length on my bows but the methods for adjusting draw length vary depending on what bow you have. I’ve posted several videos on adjusting the draw length for bows from a few different manufactures.
In general, draw length is controlled by modules which are attached to a bows cams. There are two primary ways of adjusting draw length with the cam modules. One is replaceable modules, and the other is adjustable modules.
If your bow uses specific draw length modules, it will have different modules for every draw length. Most bows today do not require a bow press to change the draw length even with replaceable modules.
Your bow may come with all of the modules, or you may have to order it separately.
Hopefully, if you purchased a bow with this type, the seller gave you the correct module for your draw length.If you need a different draw length module, usually they are easy to replace. You can unscrew the modules and replace it with the correct length modules.
Other compound bows have adjustable modules. This means that the module will have a system of markings or holes, each assigned to a draw length distance. You will need to consult your specific bows owners manual to find out the corresponding set up for your draw length.
With this type of modules, you remove the module screws, turn the module to the desired draw length distance and reattach the screws.
How to adjust draw length on a Bear compound bow
How to adjust draw length on a Hoyt compound bow
How to adjust the draw length on a PSE compound bow
How to adjust the draw length on a Diamond compound Bow
How to adjust the draw length on a Bowtech compound bow