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How To Measure A Longbow String

Archers that are just getting started with their traditional bow adventure often find themselves stuck with the question of how to measure a longbow string.

But what if we told you that the process is not as hard as you think it is? Stick around to find out!

So, according to AMO, which stands for Archery Manufacturers Organization, you can easily measure the bowstring of a longbow by considering the length of the bow.

And for most of the bows, there will be an AMO label, which should be right around the grip area.

However, the number that is on the AMO label does not directly state the length of the bowstring. Instead, it is the AMO length of the bow.

Now, you might be wondering how we measure the longbow for a string with the AMO label, right?

Well, it's easy! You just need to deduct 3 inches from the label's number. For example, if the AMO label states 63 inches, it does not mean that you will need to use a string that is 63 inches.

Instead, you need to deduct three inches and use a line that is 60 inches.

But what if there is no AMO label? Can you figure out the AMO length with the label? Well, yes, you can!

Here are the steps to find bow string length without AMO Label:

Step 1: Position the Bow

First and foremost, you should lay the bow down. It should be face down on a flat surface.

Step 2: Take Measurements

After positioning the bow, you just have to get a tape measurer and take measurements from one bow string groove to another. Here, you will be factoring in the distance across the limbs of the bow.

Do not go through the grip area. Instead, follow the bow's natural line, also known as the belly of the bow.

That's it! You need to go through those two steps to get the AMO measurement. Again, deduct 3 inches from the number that you get to end up with the string measurement for the bow.

Take Measurements of Your Longbow

How To Measure The Bow String Without AMO Measurement

You do not have to rely on the AMO measurement if you do not want to. There is another way to measure the bowstring. For this method, you need to go through these two steps:

Step 1: Prepare the Bow

Place the bow on ¼ inches pegs and set the tension at 100 pounds. Leave the bow like that for about 20 seconds.

Step 2: Measure

After 20 seconds, you need to start taking measurements from the outside of one peg to the outside of another. The measurement that you will end up with is the length of the string for that bow.

For this method, there will be no need to subtract anything from the measurement. For example, if you have ended up with 63 inches after measuring the bow in that state, you will need a string that is 63 inches for the bow.

A common mistake that many makes, in this case, is taking the measurement from the inside of the peg. You will not end up with the right measurement if you do so.

Therefore, keep this in your mind when you are following this method.

Can You Take Measurement from an Old String?

Of course! If you have an old string for the longbow, you can take measurements from that one. However, this method will only be helpful if you are upgrading your old line.

If you do not have a string for the bow you want to work with, you have to resort to the AMO or manual bow measurement.

Final Words

Are you still asking yourself how to measure a longbow string? Well, things will be pretty easy if you have an AMO label on the bow. You just need to subtract the number by three.

But, if the label is not there, you should resort to manually measuring the bow. Just follow the steps we have gone through properly, and you should be all good!

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