I am a keen hunter and have been a crossbow enthusiast for the past five years.
What Do I Want to Achieve With My Crossbow Bolt?
Your objective when looking for a great crossbow bolt is that, first of all, you are precise over a variety of distances.
Obviously this depends on your quality and experience as a hunter, but with the wrong bolts you may have varying degrees of efficiency.
You also want a crossbow bolt which helps to achieve high penetration when hunting. This is essential for a couple of reasons.
First of all, it's more likely to do sufficient damage to achieve a kill.
Second of all it's more likely to pass all the way through the animal, leaving a larger wound and more obvious blood trail to facilitate tracking the animal down afterwards.
Understanding your Bolts
Vanes or fletchings are the traditional 'feather' at the back of the bolt.
They weigh little, anywhere from 5 to 10 grains, and are designed to guide the arrow to its target.
The best way for an arrow to maintain its precision is to rotate perfectly, thus maintaining its course. This action of a bolt rotating around the very centre of an arrow shaft is called centricity.
For the vanes to improve the centricity of the arrow, most designs have what are known as off-set or helical fletchings, which force the arrow to start spinning.
The bigger the fletching at the back, the more drag. To counteract the drag you need your arrow to be primarily balanced towards the front.
FOC: Weight Forward of Center
FOC stands for forward of center. It means that instead of an arrow being balanced perfectly down the middle, the weight is shifted towards the front.
More FOC is good so that the arrow allows itself to be guided by the fletchings at the back.
More FOC also increases penetration of the animal, which is good for several reasons.
It's more likely to bring an animal down by shattering bone or by heavy impact. It increases blood loss, so the animal dies quicker, as well as easily being able to track it down later.
Lots of hunters are really keen to improve the speed of their arrows (FPS). To achieve this, many of them decrease the mass of their arrows.
what they fail to take into account is that by reducing weight they are also reducing power. This may lead to reduced penetration, which depending on what you use your crossbow for, may not be a good thing.
What's more, an increase in mass will improve the bolts accuracy over longer distances, as the bolt is not so easily manipulated by crosswinds.
Also, take into account that a heavier arrow needs a larger fletching to successfully guide it.
Crossbow bolts normally measure anywhere from 16 to 22 inches long.
The size bolt you buy will be primarily guided by your crossbow and its power stroke. Check what size bolt your crossbow works with.
You can vary the bolt length though. A shorter length is stiffer and less flexible. This is better for penetration. These bolts will also accelerate faster.
So why not go for very short bolts? The problem is over long distances a shorter arrow will lose its velocity much faster. You're essentially looking for the right trade-off.
Field-Tips and Broadheads
All bolts need a 'head' to be inserted in the end. The type of head that you purchase depends on your intentions for your crossbow.
If you're just practising then you'll want field-tips. Field-tips are simple and effective, with little embellishment. They fly true and are not easily influenced by the wind when flying.
A broadhead is for hunting. It has an embellished and sharpened point to pierce an animals skin and cause as much damage as possible.
There are two types, fixed-blade broadheads and mechanical broadheads.
Mechanical broadheads are an evolution of the traditional fixed-blade broadhead. The idea is that they fly like field-tips without interference, until the last moment when upon impact they open up some mechanical teeth in order to inflict enough damage to wound the animal.
Both field-tips and broadheads typically weigh between 100 and 150-grains. You can change the weight to customise your arrow, and its FOC.
When purchasing bolts, check to see whether field-tips are included. It's unlikely they will come with broadheads.
The nock is the point of the bolt where it meets the string on the crossbow.
There are two traditional designs - half-moon nocks and flat nocks.
A flat nock has a wide surface area whereas a half-moon nock has a designed shaped around the string and sits perpendicular to the index vane.
Half-moon nocks are good because they are built for the string to catch them well.
What can happen however, is that half-moon nocks are badly positioned to fire. This can cause accidents.
More recently from a popular brand called TenPoint we have seen the 'omni-nock'. It catches the string well thanks to multi grooves, while eliminating injury-related mishaps.
The right arrow can make a difference to your crossbow setup. For a lot of hunters, once they find some that they like, they stick with them for many years.
The key is finding a balance between the arrow mass, FOC weight, and vane size for the game you're hunting.