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Types of Crossbow Bolts- Based on Material, Weights & Nocks

types of crossbow bolts
Written by Erik Himmel

The story of William Tell makes for a fascinating copy. A bearded, sturdy man, crossbow over his shoulders, who refused to take his hat off to the Hapsburg Duke. The Duke’s bailiff placed an apple on his son’s head and ordered Tell to shoot it down. If he failed both he and his son would be put to death. Tell did shoot the apple off without any harm coming to the boy. And so was launched Switzerland’s struggle for Independence. From medieval skirmishes and battlefields, the crossbow has survived till modern times as a hunting tool and as a sport. It has greatly substituted the bow and arrow which require greater dexterity, strength, and training in their use.

Different Types Of Cross Bolts

A crossbow has to propel a projectile. The modern cross bolt is simply an arrow or as it is otherwise called a quarrel. The bolt itself is of square head design. The bolt length can be significantly shorter than the traditional arrow. Hardwood is used in their fabrication and the bolt’s front end is of special steel.

Crossbow bolts are fitted with vanes that are two-sided and spaced 180° apart. A variation also in use is 3 vanes, the third being placed on top of the bolt between the other two.

To consolidate bolt dimensions:

  • The length should be 12.5“
  • 3” is the length of the head
  • Backend length is about ½”

In choosing the right crossbow bolt, refer to the crossbow manufacturers’ recommendation. They are pros at this and will advise you sensibly as to what bolt is most suitable for your crossbow. Two things are at a stake here; the warranty and personal safety.

Military Crossbow Bolts

These types of crossbow bolts are designed to up both range accuracy. They sport a pyramidical head which is a whale lot dynamic than broadheads.

The bolts have square-faced heads. A bolt head is  as below:

Military-Crossbow-Bolts

Slurbow Bolts

While on the types of crossbow bolts, the slur bow bolts have a pedigree of invention. The barrel is generally wood or metal. The bolts design has its roots in the emergence of the pistol. Advanced hunters are singing psalms about slur bow bolts. They have earned a name as the bolt well suited because of its right correlation between size and speed leading to excellent game hunting.

And then as always, you have the purists who prefer DIY crossbow bolts. It’s really no big deal but we will talk about it later.

People sometimes ask about steel crossbow bolts. A crossbow bolt is a delicate balance. A bolt too heavy or a head overweight can tip the scales. With modern, superior materials at hand, steel is not an option. The upkeep of a steel crossbow bolts is time-consuming. So it is generally not preferred.

Crossbow Bolts Based On Material

1. Carbon

Carbon fiber is beyond doubt stronger and deep penetrating. They are a tad heavy on the purse.

Carbon bolts have reduced flexion which translates as the ability to stop suddenly on impact with the least stress on the shaft possibly weakening it. So what we have is a bolt tailor-made for repeated use without any fear of material integrity mismanagement.

2. Aluminum

Aluminum is mostly chosen because it is inexpensive. They are also handicapped with a lack of strength and are easily bent. Their durability is not great. They are employed for practice mostly.

Crossbow Bolts Based On Weights

Let’s figure out what is meant by ‘grain’ before moving on.

When buying a new bolt, the maker will provide you the weight is so many grains, for example, 300, or he may give you the GPI value which is short for ‘grains per inch.’ If the total length of the shaft is 20 inches and the GPI 15, The weight of the bolt is 20×15=300 grains. Multiplying grains by the coefficient 0.0648 yields the weight in grams, in our example 300×0.0648=19.44 grams.

Lightweight Bolts

Make sure with the manufacturer if a lightweight bolt is suitable for your specific crossbow.

Lightweight bolts are those with 350 grains or less, with 300 grains as a limit. They describe flatter trajectories and have a high airspeed. Obviously, because of the lightweight, crosswinds will throw them off course. Wind, range and the elements will affect them adversely too. To add to these disadvantages, wear and tear on the crossbow increases, the vibration caused is above average and it is noisy that can spook your prey into fleeing.

Contrarily, they are good for competition shooting.

Penetration is poor so it is suitable for small games only. When going hunting, change the field tips for broadheads.

Standard-Weight Bolts

Standard-weight bolts are in the range of 350-400 grains. These are the most versatile of all bolts for crossbows. It’s a great all-purpose bolt. The slight increase in weight ensures more transference of power from string to bolt.
It goes easy on the bow cutting back on wear, easing the noise and racking up target penetration.

It is less affected by the natural elements and flies true with a great deal of accuracy. They are in the perfect slot for game hunting.

Heavy-Weight Bolts

These are upwards of 400 grain and pack a pretty punch owing to their high kinetic energy and all the pros and cons that go with that. It can penetrate deep, is unaffected by the wing and other adverse weather conditions. Downrange, the trajectory suffers calling for expert judgment.

A heavier game such as deer, elk, etc is prime targets. They are almost noiseless, so consider using a rangefinder to assist your assessment.

Bolt Length Matters

Bolt Length Matters

Bolt lengths are typically 16-24 inches. As explained earlier on, the GPI (grains per inch), is reckoned as the weight indicator of the bolt and ultimately decides on total weight.

Having a similar GPI, a shorter bolt will fly faster than a longer bolt. As an example, one manufacturer screams his 20-inch bolt is the best.

Based On Nock Types

Based On Nock Types 1

Based On Nock Types 2

Above are the different nocks and their purpose is evident. But still, a brief introduction will not be amiss.

It is the tail-end part of the bolt and provides a launching pad. It is fabricated of durable plastic or aluminum and its importance cannot be overemphasized as this is the point where energy transference occurs.

A well-recommended nock for the day is the half-moon or half-moon hybrid and by night, the lighted nock of course.

Let’s run through them briefly.

Flat

The simplest, a traditional design dating back to its origins. It does require some practice though.

Half-Moon

This nock provides a groove for secure placement of the string. The string, other than slipping out, allows the right placement of the fetchings; imparting a smooth trajectory and accuracy.

Hybrid half-Moon

This is a new adaption and the closest is the multi-grooved nock in the figure. It is essentially a combination of the flat nock and the half-moon nock.

Lighted Nocks

Another recent development, it lights once fired and makes it easy to retrieve. A must for night hunters.

Apart from all these types, you can also make crossbow bolts all by yourself.

A William Tell ushered independence with his crossbow. If that is not impetus enough, think harder. Leave aside hunting, just practicing with a crossbow in your backyard is a formidable exercise in instilling focus. No mere coincidence that it has been a part of the Olympics and other sporting events. Why don’t you give it a shot?

About the author

Erik Himmel

A Part-Time Firearm Instructor

Hi, this is Erik. We all know firearms are dangerous, but only when one doesn’t know how to use and care for them. I have 15+ years of experience with different types of guns and for the last 10 years, I have taught numerous people how to hold and shoot a gun while staying safe and keeping the surroundings unharmed. My neighbors are some of my biggest admirers who enjoy talking to me about their guns, firearms safety and maintenance.

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