The Sig Sauer P320 is a popular firearm that has gained a loyal following among gun enthusiasts. One of the reasons for its popularity is its modular design, which allows users to customize the firearm to their liking. The fire control unit (FCU) is a particularly important component of the P320, as it houses the trigger, springs, and other important parts that make the firearm function.

For those who want to take customization to the next level, purchasing an 80% Sig P320 FCU is possible. This means the FCU is only 80% complete, and the user must finish the remaining 20%. This can be a challenging task, but it allows for even greater customization and personalization of the firearm. With the right tools and knowledge, anyone can complete an 80% Sig P320 FCU and have a truly unique firearm.

It is important to note that finishing an 80% Sig P320 FCU is not for everyone. It requires a certain level of skill and knowledge and access to the right tools. However, for those who are up for the challenge, it can be a rewarding experience that results in a truly one-of-a-kind firearm.

What is a Sig P320 Fire Control Unit?

Overview of Sig P320 Fire Control Unit

The Sig P320 Fire Control Unit (FCU) is the serialized component of the P320 handgun. It contains the trigger, slide release, and other important parts that make the gun function. The FCU is available in different configurations, including a complete unit or an 80 percent version that requires some assembly.

The Sig P320 is known for its modularity, and the FCU is a key component that allows for customization. The FCU can be swapped between different grip modules, slides, and barrels to create a personalized firearm. The FCU is made of high-quality materials, including titanium nitride, which is known for its durability and corrosion resistance.

Why an 80 Percent Sig P320 Fire Control Unit?

The 80 percent Sig P320 FCU is a popular option for gun enthusiasts who enjoy building their own firearms. The 80 percent version requires some assembly, but it allows for greater customization and can save money compared to buying a complete unit.

Building an 80 percent FCU requires some technical skill, but it can be a rewarding experience for those who enjoy DIY projects. The 80 percent version is also legal in most states, as long as it is not completed and used as a firearm without proper licensing and registration.

In summary, the Sig P320 Fire Control Unit is a key component of the P320 handgun that allows for customization and modularity. The 80 percent version is a popular option for gun enthusiasts who enjoy building their own firearms and can save money compared to buying a complete unit.

How to Build an 80 Percent Sig P320 Fire Control Unit

Tools and Materials Needed

Building an 80 percent Sig P320 Fire Control Unit (FCU) requires a few essential tools and materials. Here’s what you’ll need:

  • A Sig P320 FCU Jig
  • A drill press
  • A drill bit set
  • A milling machine
  • A vise
  • A torque wrench
  • A hammer
  • A punch set
  • A Sig P320 FCU parts kit
  • A Sig P320 FCU insert

Step-by-Step Guide

Once you have all the necessary tools and materials, it’s time to start building your Sig P320 FCU. Here’s a step-by-step guide:

  1. Install the FCU Jig into the milling machine and clamp it securely in the vise.
  2. Secure the Sig P320 FCU insert onto the jig using the supplied screws.
  3. Use the drill press to drill the required holes into the insert.
  4. Use the milling machine to mill out the necessary areas of the insert.
  5. Install the Sig P320 FCU parts kit into the insert, following the manufacturer’s instructions.
  6. Use the torque wrench to tighten the screws to the manufacturer’s recommended torque.
  7. Use the hammer and punch set to install the trigger pins and other small parts.
  8. Test the FCU for function and safety.

Building an 80 percent Sig P320 FCU can be a challenging but rewarding process. With the right tools, materials, and instructions, anyone can build their own custom FCU for their Sig P320 handgun.

Legal Considerations

Federal and State Laws

Navigating the legal side of the Sig P320 Fire Control Unit (FCU)? Here’s the lowdown. The FCU is viewed as a firearm by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). This means all firearm laws apply.

At a federal level, the FCU dances to the same tune as any other firearm. It needs to play by all federal rules during manufacturing and selling. Plus, any tweaks you make to the FCU must stick to federal law.

Your state might add its own set of rules to the mix. Doing your homework on local laws keeps you in the clear. Some states have their own limits on selling or owning certain firearms or parts. Staying clued in keeps you on the right side of the law.

Serial Number and Registration

Another legal facet with the Sig P320 FCU is all about serial numbers and registration. Federal law demands all firearms, including the FCU, to bear a serial number. Crafting your own FCU? You’ll need to score a serial number from the ATF to legally sell or pass it on.

Besides serial numbers, some states have registration rules for firearms. Check out your local laws to see if your FCU needs to be registered.

Staying savvy about the legal angles of the Sig P320 FCU is crucial. By staying in line with all the rules, you can enjoy your FCU with peace of mind, knowing it’s all above board.

Troubleshooting

Common Issues

When building an 80% SIG P320 Fire Control Unit, there can be some common issues that builders may encounter. Here are some of the most common issues and their solutions:

  • Trigger not resetting: This can be caused by the trigger bar not being installed correctly or the trigger return spring not being installed or installed incorrectly. To fix this, ensure that the trigger bar is properly installed and the trigger return spring is installed correctly.
  • Hammer not cocking: This can be caused by the hammer spring not being installed correctly or the sear spring not being installed or installed incorrectly. To fix this, ensure that the hammer spring is installed correctly and the sear spring is installed properly.
  • Slide not locking back: This can be caused by the slide stop lever not being installed correctly or the slide stop spring not being installed or installed incorrectly. To fix this, ensure that the slide stop lever is properly installed and the slide stop spring is installed correctly.
  • Safety not functioning: This can be caused by the safety lever not being installed correctly or the safety plunger not being installed or installed incorrectly. To fix this, ensure that the safety lever is properly installed and the safety plunger is installed correctly.

Solutions

To troubleshoot these issues, builders can refer to the manufacturer’s instructions or seek advice from online forums and communities. Additionally, builders can double-check their work and ensure all components are installed correctly and properly functioning.

In some cases, builders may need to replace certain components or seek professional assistance to diagnose and fix the issue. It is important to take the time to troubleshoot and resolve any issues to ensure a safe and reliable firearm.

Conclusion

Crafting a SIG P320 from an 80% FCU? A task with some grit to it. It’s not everyone’s cup of tea, but for those craving a challenge, you’ll create a top-tier firearm made just for you.

One of the best parts? You call the shots on the components. The trigger, sights, and all the other bits and pieces – they’re all your choice. Tailor-made for your shooting style, the result is a firearm that’s just the way you like it.

Then there’s the satisfaction. Nothing beats seeing your hard work shape up into a precise, functioning firearm. An accomplishment that’s a shot right on target!

Sure, it has its challenges. The price tags are time, money, and a fair bit of effort. You’ll need the right tools and knowledge to nail it. But if you’re up for it, the rewards are worth the journey.

So, crafting an 80% P320 is a game for the daring. A way to get a firearm that fits like a glove to your needs. Considering it? Just remember to do your homework and you’ll be on your way to a successful project.

Frequently Asked Questions

Where can I find a reliable 80% Sig P320 fire control unit?

There are a number of reputable sources for purchasing a reliable 80% Sig P320 fire control unit. Some popular options include JSD Supply, 80-Lower.com, and US Patriot Armory. Researching and choosing a reputable seller is important to ensure you receive a high-quality product.

What parts do I need to complete a Sig P320 build?

To complete a Sig P320 build, you will need a number of parts in addition to the fire control unit. These may include a grip module, slide, barrel, and sights. Choosing parts that are compatible with the P320 and meet your specific needs and preferences is important.

Is the Sig P320 better than a Glock?

Opinions on the Sig P320 versus Glock vary, and ultimately it comes down to personal preference. Some people prefer the ergonomics and modularity of the P320, while others prefer the simplicity and reliability of Glock. It’s important to handle and shoot both firearms to determine which is best for you.

What is the Sig P320 80% lower?

The Sig P320 80% lower refers to the unfinished fire control unit of the P320 that is not considered a firearm by the ATF. This allows individuals to purchase and complete the unit without going through a background check or requiring a license. However, it’s important to note that the completed unit is still subject to all applicable firearm laws.

Can the Sig P320 fire when dropped?

There have been reports of the Sig P320 firing when dropped under certain conditions. However, Sig Sauer has addressed this issue with a voluntary upgrade program that includes a new trigger and other modifications to prevent unintentional discharges.

What is the military’s issue with the Sig Sauer P320?

The military’s issue with the Sig Sauer P320 was related to the firearm’s reliability and safety during drop tests. Sig Sauer has since addressed these concerns with the voluntary upgrade program mentioned above.