How to determine the arrow weight? The question is answerable but there are a lot of things to consider here. Determining the weight of an arrow to a modern bow is a trickier task than it looks at first glance. It has several factors involved that must be carefully considered.
There’s a lot of physics, some measurements, and maths involved in this process. You also have other factors to consider, like the activities that you want to perform with a certain weight. All these things can be a very difficult task to research on.
But no worries reader, this is where we come in! We have compiled some ways with which you can select the appropriate arrow weight. We believe that these ways and processes will give you a better understanding of arrow weight and it’s proper calculation.
Let us dig in!
What Is An Arrow Weight?
In layman’s term, arrow weight is the weight of the arrow that you want to shoot. Normally the weight of the arrow is measured in grains. It is expressed in grains per inch and grains per pound. Common logic dictates that arrows having lesser grains per inch is good. But that is not always the case.
For instance, the Easton Bowfire's 330 shaft version weighs 9.6 grains per inch whereas the 400 shaft weighs 8.5 grains per inch. But the 400 shaft version, despite being lightweight is very weak so, tuning can be a big problem.
There are also other things such as spine rating and the type of activity that determines the arrow weight and the appropriate way to select an arrow.
Why Is An Arrow Weight Important?
An Arrow, when shot from the bow, flies with kinetic energy. The energy is produced by drawing a bow. When the archer shoots, that kinetic energy is then transferred to the arrow. The weight of the arrow is crucial in determining the speed, drop rate and whether it penetrates the target.
Every kind of archer, whether it be a newbie, a semi-pro or a competitive professional, tries to increase the performance of their arrows by using different weights.
There are three kinds of arrows: light, heavy and ideal weight. Lighter arrows fly faster and can be grouped more tight. However. they’re very hard to tune. On the other hand, Heavier arrows can resist the wind, and have greater penetration but they are slower.
If you shoot the wrong arrow weight and your arrow weight doesn’t match with your bow, it can severely damage the bow and even harm the archer in some cases. This is the reason behind the fact that manufacturers design bows for particular weights of the arrow.
Tips On How To Determine The Arrow Weight
1. Measure Your Draw Length
In case you don’t own a bow and you don’t know anyone who has it, you can follow an algorithm to calculate the draw length. In order to measure your draw length, you need to follow some steps. You also need a measuring tape and preferably a person to just help you out. The steps are given below;
- Stand Straight. Make sure to not wear any clothes that can restrict the movement of your arms and not enable you to see whether your elbows are locked. Also, do not hunch forward.
- Now, you need to spread your arms to the sides. You need to ensure that they form a straight line. Your arms should be parallel to the floor of your house.
- The third step is to get someone to measure the whole arm length. You need to measure the span of your arms i.e, the tip of one hand’s middle finger to the next hand. The tape should also be fully stretched otherwise, the measurement will not be accurate enough.
- Finally, take or convert your measurement in inches and then, divide it by 2.5. The resulting value is your draw length.
2. Calculate The Arrow Length
Selecting the proper length for your arrow used to be a complex task back in the days. But, nowadays the arrow technology has somewhat improved, the designs are very good and the process has become much simpler. You can easily take your draw length and add 0.5 to 1 inches to determine the arrow length that suits you.
So, if your draw length is 27 inches then, you need to add a maximum of 1 inch i.e, you have to purchase an arrow of length 28 inches. This will provide you with an arrow that will be long enough for clearing the front part of the arrow shelf.
You need to remember that the length of an arrow is measured from the deepest area of the nock groove, all the way to the end of the shaft. The measurement doesn’t consist of the length of your broadheads.
3. Understand Grains Per Inch (GPI) And Grains Per Pound (GPP)
GPI and GPP, although they sound the same are actually different things. They are properly described below:
Grains per inch is the standard to measure the weight of the arrow. An arrow’s GPI determines the shat weight of the arrow. It includes the length, diameter, thickness of the arrow. Arrow Manufacturers provide a detail list of GPI for their products. In terms of GPI, the arrows can be classified as:
- 5 to 6 grains per inch: Light Weight
- 7 to 9 grains per inch: Midweight
- More than 10 grains per inch: Heavyweight
Grains per pound is the ratio of the arrow’s total weight to the bow’s weight for shooting the arrow. GPP is always confused with GPI but as evident, these two things are completely different. The GPP total includes the arrow’s shaft weight, the weight of the nock, insert, point and fletchings. In terms of GPP, the arrows can be classified as:
- 5 to 6.5 grains per pound: Lightweight
- 6.5 to 8 grains per pound: Midweight
- More than 8 grains per pound: Heavyweight
4. Select The Arrow Weight
The last thing you now need to do is to select the weight of your arrow. There are many factors that the weight is going to depend upon. Some of them are explained below.
If you are a newbie and you just want to shoot arrows for fun then, this is for you. You need to first weigh your arrow in total i.e, take the weights of everything from shaft, vanes, nock, field point and insert. Take the combined weight. This weight should be around 5 to 6 grains per pound of the bow. So, if you have a 60-pound bow, you need an arrow that weighs somewhere around 300 to 370 grains.
If you are a semi-pro hunter, you want to kill animals with your arrows so, you need arrows with greater penetration. Here, you would probably need to get an arrow that weighs in between 6 and 8 grain per pound of the bow. So, for a 60-pound bow, you’d want an arrow that weighs around 360 and 480 grains.
- Gold Tip Expedition Hunter 5575 Carbon Arrows w/Blazer Vanes Mossy Oak Blaze Wraps 1/2 Dz
- 55-75 lb Range
- 8.6 GPI w/.400 Deflection
- Blazer Vanes
- Mossy Oak Blaze Wraps
In real life, you wouldn’t want to buy separate arrows for hunting and target practice, you need to consider the pricing too. So, what you can do is get arrows that weigh anywhere between 5 and 8 grains. This will enable you to do both the activities. Also, you can go for that 5-8 grain range, if you can’t find an arrow that is meant for either target practice or hunting.
These values majorly depend on your activities. One thing you should consider is not to buy an arrow that has a weight of less than 5 grain per pound of the draw weight. Doing this will not be beneficial as it can damage your bow and worst-case scenario, even void your warranty.
Wooh! Does it seem a bit overwhelming? We bet it is not, but we believe knowing these tips will help you a lot in deciding the right arrow for your bow. Note down your requirements, match with the tips, check the marketplace and then stretch to shoot. We are glad to be of your assistance.
Last update on 2020-03-29 / Images from Amazon Product Advertising API.