Introduction: Nerf Mods: a Beginner's Guide

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About: I'm Alec. I like to post Instructables whenever I get to work on my own projects. But, that isn't exactly all the time. I usually find myself pretty busy with school, so it's not often that I actually have …

Beginners can be easily repelled from the world of Nerf gun modding by seeing a modification "write-up" that seems complicated. Many modification write-ups do seem confusing at first. However, modding a Nerf gun isn't very hard--It simply takes knowledge of how a Nerf gun works and how a mod should be executed. With this knowledge, modifying Nerf guns is quite simple.

This Instructable will introduce you to the vast world of Nerf gun modifications. It covers basic concepts of Nerf gun modifications written for complete beginners--those who are interested in Nerf guns but unsure of how or where to start.

Step 1: Why Nerf?

Since this question is probably the most common response to hearing about teenagers and adults shooting each other with modified Nerf guns, This will be the very first topic I address. Most people respond to the idea of Nerfing with comments like "Aren't you guys a little too old for Nerf guns?" or "Shouldn't you guys be playing Airsoft or Paintball?" However, I believe that Nerf is a completely different experience than Airsoft or Paintball. One notable aspect is that Nerfing is much cheaper than Airsoft or Paintball. Although Paintball and Airsoft do offer a variety of guns, Nerf offers a different kind of variety: the modification aspect of Nerfing allows for customization of weapons.  For instance, one Nerf gun may be modified to shoot one dart very far or seven darts for a buckshot effect.  Multiple guns may even be combined. For instance, a secondary weapon can be integrated into a primary weapon as a backup shot when you reload your primary.

But, in the end, it is really all a matter of preference.  If you really want to read a more in-depth article about this, here's an article from NerfHaven.com - Nerf Vs. Paintball

Tippmann A-5 image courtesy of sebaraya.com
Nerf Nitefinder EX-3 image courtesy of hasbro.com

Step 2: Common Materials/Tools

Those who Nerf use a wide assortment of materials and tools to modify a Nerf gun. However, there are some of these that are commonly used among Nerfers. There is also a description of each material/tool. The descriptions are mainly there for reference.

---Materials---
  • Barreling Materials - Most all Nerf gun modifications involve barrel replacements, so make sure you have some barreling material on hand. This will be discussed later, in step 8.
  • Sandpaper - sandpaper is great for Nerf applications that involve getting rid of unwanted plastic, cleaning up messy or crooked cuts, and more. I suggest having different grit sandpaper. (See Picture 1)
  • Hot Glue Gun w/ Hot Glue Sticks - Hot glue is used very commonly in Nerf modification. Hot glue creates a fairly strong bond with most materials and dries quickly compared to most other glues used in modification. (See Picture 2)
  • Epoxy - Epoxy is a very strong adhesive that is used in some Nerf applications that require a strong bond. The bond is much stronger than hot glue, but epoxy takes a long time to fully harden (1-2 days). Epoxy may be harder to apply in large amounts in some applications. (See Picture 3)
  • Plumber's Goop - An adhesive comparable to epoxy, Plumber's Goop creates a bond similar in strength to that of epoxy. It also takes a while to fully harden, from 1-2 days. Unlike epoxy, Plumber's Goop is not a two part adhesive, which means that you do not have to mix it before you apply it. Therefore, Plumber's Goop can be easily applied in larger amounts.

---Tools---
  • Screwdrivers - If you want to modify Nerf guns, you have to open them up first! All Nerf guns are held together with screws that can be extracted with a Phillips-head screwdriver. Be sure to have multiple sizes of these. The larger the screwdriver, the easier it is to get the screws out without stripping them. However, make sure the screwdriver head fits in the holes in which the screws are housed. (See Picture 5)
  • A Rotary Tool (Dremel) - In Nerf modification, your rotary tool will quickly become your best friend. A common brand of rotary tools that people use is the "Dremel" brand. Thus, most simply refer to their rotary tool as a "Dremel." Once you get to more elaborate Nerf modifications, you will find that you will use your Dremel very frequently. It is useful for cutting, sanding, grinding, etc. (See Picture 6)
  • Hacksaw - Hacksaws are good for cutting barrels, but hacksaw cuts tend to be a bit unclean and jagged. You can use sandpaper to sand down the jagged ends of your barrel to make it nice and straight. (See Picture 7)
  • Pipe Cutters - Also good for cutting barrels. If you master the technique for cutting barrels using pipe cutters, you can consistently produce fast, straight, clean cuts. (See picture 8)

Step 3: Common Modifications List

Here is a list of the most common mods done to Nerf guns. Modifications vary depending on what type of gun you are modifying. There are two main types of Nerf guns: Spring Guns and Pump Guns. There is a simple way to classify whether a gun is a Spring Gun or a Pump Gun: how you prime the gun. A Spring Gun is primed by a cocking mechanism. A Pump Gun is primed by being pumped a certain number of times.

--- Spring Guns ---
  • Air Restrictor / Air Limiter Removal
  • Spring Replacement
  • Seal Improvement
  • Barrel Replacement

--- Pump Guns ---
  • Air Restrictor / Air Limiter Removal
  • Over-Pressure Release Valve Plug
  • Barrel Replacement

Step 4: Understanding Spring Guns (Part 1)

There are many Nerf spring guns. Although each spring gun is unique, these guns typically operate using the same mechanisms. The Nerf Nitefinder is a spring pistol that best exemplifies the typical Nerf spring gun. In Picture 1, a stock (unmodified) Nerf Nitefinder can be seen. Picture 2 shows the Nitefinder opened.

The long tube you see is the plunger tube. This is a hollow tube where air is compressed. The compressed air flows into the barrel where it shoots the dart out. The plunger tube can be seen in Picture 3.

Picture 4 shows the plunger itself. The plunger is the part of the gun that compresses the air. It has a black rubber O-ring that creates an airtight seal between the plunger and plunger tube (Picture 5). This part of the plunger with the O-ring is referred to as the "plunger head." When the orange cocking handle is pulled back to cock the gun, the plunger is drawn back. The plunger head is now located at the back of the plunger tube rather than the front. When the trigger is pulled, the spring on the plunger causes the plunger to shoot forward. This compresses the air inside the plunger tube and causes the dart to shoot out of the barrel.

Step 5: Understanding Spring Guns (Part 2)

Picture 1 is an exploded view of the barrel. The parts next to the actual barrel itself connect the barrel to the plunger tube, but also limit the air flow in the gun. Later, we will discuss these parts that limit a gun's range.

Shown in Picture 2 is the catch mechanism. It is a part that is normally over the plunger, but is shown by itself so you can see it. Picture 3 shows the plunger without the spring or catch mechanism on it. see that curved part on it? That is where the catch engages, or put in simpler terms, where the gun cocks. The curved part of the plunger, when pulled back to the catch, forces the catch up. At the end of the curved part, the spring on the catch forces the catch down. Notice that the plunger cannot move forward, because the catch keeps the plunger from moving forward. Pictures 4 and 5 demonstrate the gun in its cocked position. Note that the curved part of the plunger is stuck behind the catch.

When the trigger is pulled, the catch is forced up and the plunger shoots forward, compressing the air that pushes the dart out of the barrel. You can see how the trigger forces the catch up in Picture 6.

If you do not understand this or it is unclear, this is fine. I suggest you buy a Nitefinder for modification, as mechanisms will become clear when you disassemble the gun. Even if you don't quite know how a gun works, it is fine to open the gun, as long as you take caution not to lose any pieces. Opening the gun and tinkering with it yourself will help with your understanding of the gun's mechanisms. It is important to be careful but not to be extremely careful.

Step 6: Understanding Pump Guns

Here, the various mechanisms of pump guns are covered. The example being used in this is the Big Blast. This gun isn't actually made by Nerf, but is made by Buzz Bee Toys. It fires "missiles" and takes as little as five pumps to prime. There are four main parts on pump guns: the pump, pump tube, pressure chamber,and barrel. Shown in Picture 1 is the guns internals, labeled.

In the next picture, the gun's pump can be seen. Like the plunger of a spring gun, it has an O-ring on the front of it. This makes an airtight seal with the pump tube, shown in Picture 2. When pushed forward, the pump compresses the air in the pump tube, and a valve in the pressure chamber lets compressed air into the pressure chamber itself. This pressurizes it. When enough pressure has built up in the pressure chamber, further pumping will only release the air trying to be pumped into the pressure chamber. The object that is responsible for this air-release is called the "over-pressure release valve" and is shown in Picture 3. Additionally, you can see a close up of the pump tube and the pump inside of it in Pictures 4 and 5.

See the metal rod that the trigger is attached to in the next picture? This rod, when pulled back, releases the air in the pressure chamber. The trigger is attached to this rod, so pulling the trigger back will pull the rod back (see next picture), releasing the air in the pressure chamber . The air from the pressure chamber then travels down the barrel and fires the loaded ammo.

Again, if this is unclear, do not be too careful and try to understand everything, opening the gun will help your understanding, and it is unlikely anything will go wrong from simply viewing a gun's internals.

Step 7: Barrel Replacements Part 1: the Stefan

This is an introduction to barrel replacements.

YOU MUST FIRST UNDERSTAND THIS CONCEPT: Nerfers make and use homemade darts called stefans. These stefan darts are very cheap, easy to make, and have great performance that achieve much higher ranges than stock Nerf darts. Shown in Picture 1 is a stefan in comparison to a stock Nerf micro dart. Notice how stefans do not have a ring of rubber on the end of the dart. This allows them to be loaded in the back of long barrels. Nerf darts have a ring of rubbery material on the front. This is sometimes referred to as the "neck" of the dart. In barrels in which stefans load in the back, Nerf darts load in the front, as the neck of the dart prevents it from being pushed in farther down the barrel. The concept of stefans being loaded into the back of the barrel, often referred to as back-loading, allows the dart to achieve ranges much higher than that of normal Nerf darts. Since the dart travels down the entire barrel, it receives optimum pressure when it leaves the barrel. Also, when stock Nerf darts are front-loaded in high-powered guns, they usually end up spinning out of control.

Step 8: Barrel Replacements Part 2: the Barrel

Shown below are the most commonly used barrels in Nerf modification. However, you must first understand the use of couplers in Nerf modification. Couplers are pipe fittings used to "couple" (hence the name) two lengths of barrel material together. There are couplers for CPVC and PVC barrels. Why and how would these be used? Well, imagine if the barrel is glued in place on a gun. Every time you want to back-load stefan, you would have to put the dart in the barrel then ram-rod it to the very back of the barrel. This takes quite a while to simply load the gun and is unpractical. However, If a coupler is glued in place of the barrel, you can take the barrel out of the coupler, load a dart in the back of the barrel, then stick the barrel back in the coupler.

1/2" CPVC
  • Works with: micro stefans (back-loading) and Nerf micro darts (front-loading)
Notes:
  • Good quality material
  • Very cheap material (a couple of dollars for 10 feet of 1/2" CPVC)
  • Can be cut with a hacksaw, PVC cutters, pipe cutters, rotary tools, etc.
  • Works in 1/2" CPVC couplers
Brass Tubing
  • Works with: micro stefans (back-loading) and Nerf micro darts (front-loading)
Notes:
  • Very good quality material, gets great performance
  • Material is quite expensive (up to 5 dollars for a foot of this)
  • Can be cut with a rotary tool using a cut-off wheel. Other tools may be able to cut this, but most use a rotary tool
  • Does not work in couplers
  • Comes in many sizes, but sizes 9/16" and 17/32" are the two main sizes that Nerfers use for barrels
  • 17/32" is the more common barrel size and has a tight fit on darts
  • 9/16" has a looser fit on darts, but it works better for some people
1/2" PETG
  • Works with: micro stefans (back-loading) and Nerf micro darts (front-loading)
Notes:
  • Very good quality material, similar performance to brass barrels
  • Much cheaper than brass, sold by a vendor on this Nerf website for $0.50 a foot
  • Can be easily cut with a hacksaw, pipe cutters, a rotary tool, or even scissors!
  • Does not work in couplers
1/2" PVC (SCH40)
  • Works with: Nerf micro darts (back-loading)
Notes:
  • Good quality material
  • Very cheap material (a couple of dollars for 10 feet of 1/2" PVC)
  • Can be cut with a hacksaw, PVC cutters, pipe cutters, rotary tools, etc.
  • Works in 1/2" PVC couplers
IMPORTANT! - 1/2" PVC is larger in diameter than 1/2" CPVC. in fact, the neck of stock Nerf darts fits in the barrel. Because of this, you can back-load stock Nerf micro darts into 1/2" PVC barrels. This is not the most common barrel material. Back-loading stock Nerf micro darts into 1/2" PVC barrels does not receive ranges as great as micro stefans in a 1/2" CPVC barrel, so 1/2" PVC barrels are not commonly used. There is, however, one common use for 1/2" PVC: barrel "nesting." This is basically when one glues their brass or PETG barrel inside the 1/2" PVC, "nesting" it inside the 1/2" PVC. There are a couple of reasons for this:

1.) One may nest their brass/PETG barrel in 1/2" PVC to protect the barrel, as brass tubes are prone to denting and PETG is prone to bending.

2.) One may nest their brass/PETG barrel in 1/2" PVC so their brass/PETG barrel can be used in a coupler set-up.

Note on nesting: 1/2" CPVC will not nest in 1/2" PVC, as the walls of 1/2" CPVC are too thick. In most cases, it is unnecessary to nest 1/2" CPVC in 1/2" PVC, because 1/2" CPVC is not prone to deforming as brass and PETG are, and 1/2" CPVC works in couplers as is.

Step 9: Barrel Replacements Part 3: Replacing the Barrel

In this step, I will go over the some approaches to replacing the gun's stock barrel with other barrels that yield higher performance. Generally, the barrel replacement is what increases the gun's power the most. The barrel replacement is an essential modification and is the most common Nerf modification performed on Nerf guns.

I will go over the two most common approaches to this:

Simple Replacement (Singled)
Performing a "simple barrel replacement," referred to on Nerf websites as a "singled" gun, is when the new barrel is simply glued in place of the old, stock one. The one drawback of singling a Nerf gun, however, is that it takes longer to load a stefan in the barrel than the coupler setup. If you plan on back-loading stefans, you will have to ram the stefan down to the back of the barrel. In a Nerf war, this is difficult to use, considering the fact that you must carry around a ramrod.

Coupler Setup (Couplered)
When you "coupler" your Nerf gun, it is when you glue a coupler in place of the stock barrel. A 1/2" CPVC coupler, for instance, can be glued in place of a barrel so that 1/2 CPVC barrels can be loaded into the coupler. This way, you can take out a barrel, load a dart into the back of the barrel, and put the barrel in the coupler. This makes for faster loading. A couplered Nerf "Big Bad Bow" can be seen in Pictures 1, 2, and 3.

Additionally, setups like that shown in Picture 4 can be used with couplers. This is a simple flip-around barrel, made from gluing two barrels together. I wrapped this flip-around barrel with electrical tape to make it look cleaner. The arrows on the barrels indicate where the barrel faces when it is inserted in the coupler. Pictures 4, 5, and 6 demonstrate the flip-around barrel.

Step 10: Air Restrictor / Air Limiter Removal

Nerf limits the ranges of their guns by using air restrictors and air limiters in their guns. Removing the air restrictors and air limiters in a gun will increase the gun's range. There is not much to the removal of an air restrictor. Air restrictors can simply be thrown away once they are identified. Air restrictors almost always have the same exact shape: a small piece with three prongs found with a spring. This air restrictor assembly always includes a small spring, which should be discarded with the restrictor itself.

In spring guns: Spring guns almost always have air restrictors and air limiters. Picture 1 shows the air restrictor and air restrictor spring in a Nitefinder. The first air-limiting piece to be removed is the barrel post. The barrel post is the long rod that the stock Nerf dart slips over when it is placed in a Nerf gun. It is shown in Picture 2. The excess plastic left after that (Picture 3) can then be removed, in this case, with a drill. Before the drillng, the air had to flow through the small gaps in the two plastic pieces. Removing these air limiters allows air to flow to the dart quickly and gives the dart more range.

In pump guns: Pump guns almost always have some sort of air limiters, but they do not often have actual air restrictors. Keep in mind, air restrictors are the pieces (often with three prongs) that are located with a spring. Picture 4 demonstrates the removal of air limiters in a pump Nerf gun, specifically, the Nerf Titan ASV-1. Notice the air-limiting material structured like a grate. These air limiting "grates" reduce the Titan's range because air is forced to flow around the air limiters. The author of the picture used a Dremel with a cutting bit to remove the air limiting "grates."

Picture 3 courtesy of NerfHaven user Gengar003
Picture 4 courtesy of NerfHaven user hereticorp

Step 11: Spring Guns - Spring Replacement

Recall from Step 4 that in spring guns, it is the spring that causes the plunger to shoot forward. The plunger is the part of the gun that compresses the air to shoot the dart. So, if the stock spring is replaced with a stronger spring, the plunger will be able to compress the air faster, because there is more force behind the plunger. Although the spring replacement is an effective modification, it does have one drawback: using a stronger spring could cause the barrel to detach from wherever it was glued. However, if you use a strong barrel setup, using a stronger spring should be harmless. Keep in mind though, you do not want to pick a spring that is too strong; there must be limits if you want to keep your barrel from detaching.

Replacing the spring on a gun is very simple. You first must choose your spring. If it is necessary, you must cut down your spring to a length very close to that of the stock spring. A spring should be cut either with bolt cutters, or a Dremel with a cut-off wheel attachment. Other tools might break if used to cut a spring. Once your spring is cut, it is ready to be put in your gun. You can remove the plunger head (usually by unscrewing it) then take out the old spring. You can then put the new spring in its place. Other approaches to spring replacements include adding an extra spring and even stretching the stock spring. However, stretching your spring can cause it to break later, so it is not recommended by experienced Nerfers.

Step 12: Spring Guns - Seal Improvment

Spring guns use an O-ring to create a seal against the plunger tube. This seal, hoever, is not perfectly airtight. Although it does not seem like much, improving the seal by the slightest bit can really make a difference in range. There are three common methods to this:

Method 1: Simply replace the stock O-ring with another O-ring that has a better seal. O-rings can be purchased at a hardware store. Make sure that your new O-ring is not too large, because you want to have a good seal while keeping the ability to have the plunger slide around comfortably in the plunger tube. (Picture 1)

Method 2: Add a second O-ring to the plunger head. This method creates a great seal because there are two seals in the plunger tube. (Picture 2)

Method 3: Add a thin layer of electrical tape where the O-ring originally was. Then, put the O-ring over that layer of electrical tape. This stretches out the O-ring to a slightly larger size. In this plunger (Nitefinder) you do not even have to tape all the way around the plunger head. The layer of tape must be thin enough to allow the plunger to slide through the plunger tube comfortably. (Picture 3)

Step 13: Pump Guns - Over-Pressure Release Valve Plug

All pump guns have Over-Pressure Release Valves. As mentioned in Step 6, this valve leaks air when the pressure in the gun is too high. So, for instance, if you pump a gun up to 35 PSI, further pumping will not result in any more pressure going into the gun. This is because the air you are trying to pump into the pressure chamber is just leaking out of the pump tube. This valve can be plugged to achieve higher pressures in the pressure chamber. This higher pressure results in a much higher range in Nerf guns. However, if they perform this mod, you must be careful. Pumping your gun way beyond pumping limit can result in your pressure chamber rupturing. Then, your Nerf gun will not function and will be nearly impossible to repair.

The actual modification is extremely simple. First, find the hole in the head of gun's pump. This hole is where the valve is situated. Using a hot glue gun, place a bead of glue over the hole, and once it dries, you're done! Just remember, be careful with plugged OP valves, you do not want to break your gun.

Step 14: Where to Start Your Modding

You've read the basics, so it's now time to start modding! I will point you in the direction of the NerfHaven Modification Directory. This collection of modifications is sorted by gun in alphabetical order and is hosted by NerfHaven's Blue.

NerfHaven Modification Directory

The more modifications you read, the more knowledge you gain. Just by reading some modifications, you'll learn a lot. As for your very first modification, I suggest modifying a Nitefinder. Nitefinders are cheap, easy to modify, and get great ranges for a Nerf pistol. My first modification was Gengar003's Couplered Nitefinder Mod.

And an important note: NerfHaven is a great website for Nerf gun modifications, but please do not make an account and start posting... amateurish topics. The NerfHaven administrators are usually short on patience, and users who relentlessly post topics will not be tolerated. So please, if you get an account, read around and get a feel for NerfHaven before posting.

I hope you enjoyed my guide, and have fun Nerfing!