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FNS 40/9 Parts Kit (Guide)

If you are 3D printing the FN FNS 9 or FNS 40 you are going to need an FN FNS parts kit.

The FN FNS 40/9 is a popular American-made hand pistol that provides accurate shooting and several attractive features.

fns 40 9 parts kit assembeld
fns 40 9 parts kit breakdown
FNS Completion Kit

It’s ideal for many uses, including target practice and self-protection. Anyone who currently has one of these pistols may want to order a new or replacement parts kit to ensure they get the best performance and reliability from their gun.

Keep reading to learn more about this handgun and the parts kit designed to be compatible with it.

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FN FNS Parts Kit Components

This is a pulsar model for many individuals looking for a powerful yet well-designed pistol. These features are included in this kit.

Slide Assembly

The FN FNS .40 Caliber pistol features a slide assembly complete with an extractor and firing pin. The assembly comes complete and ready to install with all the necessary parts.

fns 40 parts layout
FNS 40 / 9 Full Parts Kit

The parts included in the kit include a recoil spring assembly with three dot rear notch sights. A cold hammer-forged barrel and stainless steel body construction. The slide assembly

Recoil Rod Assembly

This gun kit also comes with the FNS recipe spring guide assembly. It’s made from durable steel and comes in a black finish, and is used to contain recoil.

Cold Hammer Forged Nitrided Barrel

The nitride barrel is more durable than most other barrel types. This material is also very resistant to corrosion and lasts longer, in general, with a higher degree of accuracy.

Tritium Night Sights

These tritium night sights are installed on the slide of the pistol. This feature allows you to see in all types of lighting for more accurate aiming and shooting.

Lower Parts Kit

This kit also provides you with the complete lower parts assembly without the actual receiver.

.40 Caliber Magazine

This kit also comes complete with a 14-round .40 caliber magazine.

Backstrap Inserts

When you order this pistol kit, you also get two different backstrap inserts.

Owners Manual

This kit also includes a complete owner’s manual that provides a guide for how to assemble the pistol, proper use, and additional information about owning the pistol, including contact information and any warranty details provided by the manufacturer.

Factory FN Hard Case

The hard case for the FN FNS .40 caliber pistol is perfect for keeping your gun securely in place. It comes with a recessed space for your pistol and sturdy materials that ensure it stays protected and secure when you’re not using it.

fns 3d printed parts
3D Printed FNS 40

This kit offers the buyer almost everything they need to begin operating their FN FNS 40/9 pistol.

Additional Features (3D Printed FNS)

There is the option to fit the pistol with additional features. However, there are only a few options currently. This gun does have the capability to house lasers and sights for a more customized experience when opening it.

About the FN FNS 40/9 (Parts Kit)

The FN FNS is a semi-automatic pistol made by FN America. This particular model supports .40 Smith and Wesson ammunition or 9X19 Parabellum. This particular model features a hammerless short double-action trigger and a stainless steel barrel.

This pistol is also designed for right-to-left slide stops and magazine releases.

The FN FNS is a semi-automatic hand pistol with a polymer frame. It offers a short recoil and pre-set striker. It takes .40 caliber S&W or 9×19 Parabellum ammunition cartridges. Some additional features of this pistol include a stainless-steel forged barrel and sights with a fixed three-dot sight. Another feature worth mentioning is the loaded indicator on the right side of the gun.

Safety features that buyers find appealing are out-of-battery safety. If the slide is not pulled completely forward, it won’t release the striker on the gun. There is also a safety pin. This feature prevents the primer from being hit by the sticker unless the gun operator pulls the trigger.

There’s also a safety feature that prevents the pistol from firing by preventing the sear from letting go of the striker without pulling the trigger. Finally, the firing safety prevents the pistol from firing unless you pull the driver.

This pistol also holds a total of eighteen rounds. In terms of ammo, it can handle most types, ranging from the least expensive to the most, with equal care. Engaging the safety of the gun is simple but requires some effort. Disengagement is even easier. It also allows the user to easily fit it with additional sights and lasers.


Here are a few points of information on the 3D printed FS FNS pistol. Fun reviewers have closely compared it to the Glock 19. In terms of its appearance, the FN FNS has a slightly different shape on the slide. The angle is more pronounced than on the Glock. It also has more curved features and a larger magazine.

Overall, the design of the gun is more solid and sturdy. When it comes to breaking down the pistol, it breaks down like many comparable guns by pulling the slide and twisting the takedown. Return the slide, then pull the trigger and push the slide off the gun. The benefit of this method is that you’re forced to check the chamber first for safety. Cleaning is also simple and straightforward.


To assemble the FN FNS 40/9, place the slide upside down. Insert the barrel and then the spring. Compress the spring to insert it into the locking position at the bottom of the barrel. Then you line up the slide with the frame. Start at the front of the metal rails. Slide the frame and slide together until it locks. Put the lock in the three o’clock position. Pull back the slide. Pull the trigger to check that it’s operating correctly.


Individuals interested in purchasing this FN FNS 40/9 pistol kit can expect to get a quality product that’s highly reviewed by experts and everyday customers alike. There are plenty of safety features, and it is easy to assemble and disassemble for cleaning.

There are a few features that make it stand out from similar pistols, such as the Glock 19, but they are what make this choice stand out from the crowd. The price point for this pistol is slightly higher than many in its class, but the additional benefits are worth the investment in safety and reliability.

Consider all the features that come with the kit to determine if it’s the right choice for your particular needs. It’s ideal for personal and home protection and makes an excellent gun for both beginners and intermediate shooters who want a gun that’s simple yet reliable and less complex than many out there for sale.

To get started, place an order for the FN FNS 9/40 parts kits and explore for yourself the features this pistol has to offer buyers.

Written By

Cody Y.


Cody is a staff writer for 3D Gun Builder.

Cody brings years of experience in firearms, 80% builds, 3D printing, and internet security.

He owns six 3D printers and enjoys spreading his knowledge of modern day gun smithing around the world.

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