How To Measure Your Bow Draw Length

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Anybody who’s a bit interested in archery has come across the concept of draw length. It’s basically the distance you have to pull the bowstring through to come to full draw. When purchasing a new bow or tuning an old one, it’s really important to check the length of the bow and see that it fits your physical needs.

A draw length set too high can ruin your archery form, make it hard to anchor correctly, and ruin your average group size. It’s worth learning about it and setting your bow accordingly.

The bow’s draw length is the distance the bowstring is pulled from the rest position to a full draw. The most common way to measure what your draw length should be is to measure your arm-span and divide it by 2.5 (the wingspan method).

Adjusting your bow to fit your needs is really important for your posture and overall form. I suggest you read about measuring your draw weight in the post I’ve written about it as well. Both posts complete each other, because the main adjustable settings on a compound bow are the draw length and draw weight.

In this post, we’re going to discuss how to measure your draw length, how to set it on your bow, and why you should care about it. So let’s go.

What is the draw length on your bow?

Unlike traditional bows, compound bows are designed to be drawn up to a certain distance. The distance between the bowstring’s natural place and its location when fully drawn is called the draw length. This length is engineered by the mechanical set up of the bow.

The thing is, every archer’s physical size is different and requires a different setting on the bow. You have to adjust your bow to fit your size. We’ll discuss ways to find what your ideal distance is later in this post, but it’s quite easy.

The full draw position on the bow is basically the length it’s designed to be shot from. You should only shoot a full drawn bow. At full draw, you feel resistance from drawing it further, and it’s really easy to tell when you should stop. This force that stops you from drawing the bow further is usually referred to as “the back wall”. You shouldn’t try to pull your bow over this limit forcibly.

Draw length on recurve and traditional bows

Like I mentioned before, traditional and recurve bows don’t have a back wall like compound bows do. They do have a proper draw length, which they are at peak performance at. Anything below that span will mean slower arrows, and anything above it will mean heavier draw weight but poorer accuracy.

If you’re shooting a longbow or a recurve bow, the calculation of the draw length is a bit different. It’s harder to notice if you have an incorrect length on them, but it’s as important that you make sure to get a bow that fits your physical needs.

Measuring your archery draw length

There are a lot of ways to find your ideal draw length. They rarely agree. Your perfect range is simply the one you feel most comfortable with, and that your shots are most accurate with. I’m going to detail a few ways to find you draw length, but remember that their results are just a starting point.

I suggest you decide on a method and find your draw length through it, but also play around, try adding and subtracting half an inch and see which feels most natural to you. When you find a distance you are comfortable with, stick with it.

The first and most common way to find your draw length is the arm-span method. It’s quite simple: stand straight and lift your arms to a T position, palms facing forward. Now measure the distance between the tip of your left middle finger and the right one, and divide it by 2.5. Don’t stretch too much while taking this measurement. The wingspan method is the simplest one and is surprisingly accurate.

The standard way to measure draw length (AMO method) is a bit more complicated. You basically take a bow and draw it to full draw. First, measure the distance between the grip’s pivot point (farthest part of the grip) to the nock point (where the back of the arrow rests). This length is typically called “true draw length”. Adding 1.75 inches to the true draw length will give you the AMO draw length.

The arm span method gives a good indication of what your draw length is and is much simpler, so I’d use it. Many archery shops have other ways to find your ideal span more accurately, for example by using a draw length check bow.

I found a really helpful video that explains both how to check your eye dominance and your draw length of a bow. It details the arm span method and more.

It’s worth noting that if you use a traditional or a recurve bow, the measurements are a bit different. These bows don’t have a stopping mechanism like a compound bow, but they do have a distance they’re designed for. To find your traditional and recurve draw length you should add about 1 inch to the arm-span calculation.

What happens if your draw length is too long?

Many archers overestimate their ability to perform with a high draw length. The main reason for that is that they want to shoot faster arrows – but they are sacrificing their archer form for that. Having some added speed (of about 10 fps per 1″ draw length) but sacrificing your comfort and shooting form is a bad trade.

Having a draw length set too high either causes your arm to overextend and mess the anchor point. This basically means that your body will not be in an ideal position when shooting, which will translate into poor accuracy.

I suggest you measure your draw length every time you tune your bow, and set it accordingly. This will enable you to perform with an ideal shooting form. It’s better having the length set too low than too high, because your form will suffer less from that.

If you’re shooting a recurve bow or a longbow, it’s interesting to note that overdrawing a short bow is worse than underdrawing a long bow. With these, shooting over the ideal draw length of the bow means a significant increase in the draw weight, but much worse accuracy. Shooting under the ideal length just means you’re not taking advantage of the full capabilities of the bow.

In any case, it’s important that your bow is set to a draw length around your physical size. It doesn’t have to be exact but it should be a ballpark.

How do you adjust the draw length on a compound bow?

Not all compound bows allow for changing the draw length. It depends on the cam system installed on the bow. Most compound bows that are sold with adjustable cams are advertised as such, but they are pretty common. Actually, all the bows I’ve recommended in my recommended compound bows article have adjustable draw lengths, so it’s pretty standard.

If you have adjustable cams or modular cams, changing the draw length on your bow is pretty much a matter of changing the tightness on a screw. Adjustable cams allow for a specific range, while modular cams allow for multiple specific draw lengths. Modular cams are the most common type in the market nowadays.

In most cases adjusting them doesn’t require pressing the bow, but you’ll have to consult the manual or your bow producer to know for sure. If you bow requires a bow press, I’d suggest you go to a bow shop and hire them to help you tune the bow.

If you have draw length specific cams installed on your bow, you’ll have to purchase different cams and install them to change the distance. They come at different draw lengths. This isn’t easy to do, so I’d suggest going to an archery shop if that’s the case. Expect to pay around 80$-100$ for new cams.

Conclusions

It’s important that you measure your draw length and adjust your bow to fit your physical size. Shooting with inaccurate draw length can ruin your posture and your accuracy. Measuring your ideal draw length is really easy in most cases – you can either use the wingspan method or go to a local archery shop. I hope this guide helped you.