Draw length calculator
What is draw length?
Draw Length is the maximum distance that you can pull back on a bow string, while maintaining comfortable and proper shooting form. The initial measurement is taken between the nocking point of an arrow, and the throat (or rear edge) of the hand grip. An additional 1¾” is then added to this number. This allows for a safe margin of overhang between the contact point on your arrow rest and your chosen arrowhead. In most cases, this final number will be the same as your recommended arrow shaft length.
Why does draw length matter?
Your accuracy as an archer will be dependant upon main 3 factors; a natural shooting stance, a consistent anchor point, and a slow and calculated shot release. If your draw length is not adjust to the correct length, you will introduce uncontrolled variables into your shot process. This will ultimately reduce your accuracy.
If the draw length is too short, you may instinctually raise or tighten your shoulders to brace the bow into a more stable position. This additional tension will increase the likelihood that you will overcorrect the bow during the shot process. It should also be noted that a shorter draw length will reduce your arrow speed.
If the draw length is too long, you may struggle to hold the string against the back wall (or “let off” point) on the compound bow. This will cause a massive fluctuation in the weight held while at full draw. Not only is this bad from an accuracy point of view, this lack of control will also pose a serious safety risk to anyone in range of your arrow. To compensate for an oversized draw length, most archers will hyper-extend (or stretch) their arm outwards to create more length. In doing so, they will increase the risk of injury to themselves through contact with the string once the arrow has been released (“string slap”).
Needless to say, both scenario’s will result in a potential negative outcome. That’s why it’s important to measure your draw length as accurately as possible, and adjust your bow accordingly.
How does it affect your choice of bow?
If you’re looking to purchase a new bow, your draw length is unlikely to affect your choice between the different brand names and models on the market. Most modern manufacturers will offer their flagship bows in a range of adjustable draw weights and draw lengths to suit a wider variety of buyers. Pending local availability, the only factor that you may run into will be shipping delays – if ordering a less common size and model combination.
Buying a bow second hand is a completely different story. Due to the relatively small second hand market in Australia, your draw length may exclude you from buying some of the better second hand deals out there. While different bow limbs and new strings can be ordered, it may not always be a financially viable option.
How do I measure my draw length if I don’t have access to a bow?
The easiest way to overcome this issue will be to visit your local archery store and have them measure your draw length using the method listed above. However, this may not always be possible for those who live in more remote, or rural areas. In this case, another slightly less accurate method may be used to estimate your draw length – called the ‘wingspan method’.
The ‘Wingspan’ method
- Press your back firmly against a wall and spread your arms out to your side to make a t-shape. While doing this, make sure that your shoulders are relaxed (don’t shrug or tense them upwards), keep your fingers together, and have the palm of your hands facing outwards.
- Get a friend to measure from finger tip to finger tip across your body (in inches).
- Round the number off to the nearest inch and type it into the calculator below (or divide it by 2.5).
This calculation will get you to 1/4″ (give or take) from your ideal draw length. From there, micro adjustments can be made to your bow in order to account for user preferences and the type of release aid used.
Draw length calculator
Things to consider when making adjustments to your bow
- Always use your own release aid when testing adjustments to your bow. Different types of release aid, or a release aid adjusted to a different sized hand, will affect your draw length.
- If hunting in a cooler climate, some archers will reduce their draw length by one inch. The reduced length allows the archer to lower their shoulder, which provides greater string clearance for their lead arm. This is done to compensate for the added layers of clothing worn. If the string were to contact this clothing, the arrow is likely to travel in an erratic flight path.