Sig P320 M17 vs M18: Key Differences and Which One to Choose - CYA Supply Co.

Sig P320 M17 vs M18: Key Differences and Which One to Choose

When it comes to choosing the right firearm, the Sig Sauer P320 series has gained considerable popularity among gun enthusiasts. Two models, in particular, have been the subject of much debate - the Sig P320 M17 and M18. While both models share many similarities, there are some key differences to consider before making a purchase.

The Sig P320 M17 and M18 are both striker-fired, semi-automatic pistols chambered in 9mm Luger. The M17 is the full-sized variant, while the M18 is the carry-sized version. Both models are part of the U.S. Army's Modular Handgun System (MHS) program and have been adopted as the official sidearm of the U.S. military.

If you're in the market for a Sig P320 and can't decide between the M17 and M18, this article will provide a detailed comparison of the two models. We'll take a closer look at the design, modularity, performance, reliability, and accessories to help you make an informed decision.

Overview of SIG P320 M17 and M18

The SIG P320 is a popular series of striker-fired, semi-automatic pistols manufactured by Sig Sauer. The M17 and M18 models are two of the most well-known variants of the P320 that were designed and developed for the United States military.

The SIG P320 M17 is a full-sized pistol that was selected by the U.S. military as its new service pistol in 2017. It features a 4.7-inch barrel and a capacity of 17+1 rounds of 9mm ammunition. The M17 is a modular pistol that allows users to easily switch between different grip sizes and slide lengths to suit their preferences.

On the other hand, the SIG P320 M18 is a compact-sized pistol that was also developed for the U.S. military. It is essentially the carry-sized version of the M17 and features a 3.9-inch barrel and a capacity of 17+1 rounds of 9mm ammunition. The M18 is also a modular pistol and shares many of the same features as the M17.

Both the SIG P320 M17 and M18 are highly reliable, accurate, and easy to shoot. They are also both constructed with high-quality materials and feature a variety of safety features to ensure user safety. The M17 and M18 are both excellent choices for military, law enforcement, and civilian use.

Overall, the SIG P320 M17 and M18 are two of the most highly-regarded pistols in the P320 series. They are both modular, reliable, and accurate, making them excellent choices for a wide range of users. Whether you are a member of the military, law enforcement, or simply a civilian looking for a high-quality pistol, the SIG P320 M17 and M18 are both excellent options to consider.

Design and Modularity

Modular Features

One of the key features of the Sig P320 M17 and M18 is their modular design. Both models feature a serialized stainless steel frame that contains the trigger group, slide rails, and internal chassis system. This allows for easy customization and adaptability to meet the specific needs of the user. The grip modules can be easily swapped out with different sizes and styles to fit the shooter's hand, while the slide and barrel can be swapped out to change calibers or barrel lengths.

Grip and Frame Options

The Sig P320 M17 and M18 come with a polymer frame and a compact-length dust cover. The grip modules are available in various sizes and styles, including the AXG grip module, which features an aluminum grip module that mimics the look and feel of a 1911. The AXG grip module also features a removable grip weight that can be adjusted to balance the gun for better shooting performance.

Slide and Barrel Design

The Sig P320 M17 and M18 both feature a striker-fired system and a modular slide and barrel design. The slide is made of stainless steel and is available in various finishes, including black and coyote tan. The barrel is available in two lengths: a 4.7-inch barrel for the full-size M17 and a 3.9-inch barrel for the compact M18. The barrels are made of carbon steel and are coated with a durable nitron finish for added protection against wear and tear.

In conclusion, the Sig P320 M17 and M18 are both excellent choices for those looking for a modular and customizable handgun. With their internal chassis system, grip modules, and slide and barrel options, these guns offer a level of modularity and versatility that is hard to beat. Whether you're looking for a full-size duty gun or a compact concealed carry gun, the Sig P320 M17 and M18 have you covered.

Performance and Reliability

Accuracy and Ballistics

The Sig P320 M17 and M18 are both known for their exceptional accuracy and ballistics. The pistols are chambered in 9mm, which is widely regarded as one of the most reliable and effective calibers for handguns. The barrel length of both pistols is 4.7 inches, which allows for a longer sight radius and improved accuracy. Additionally, both pistols are equipped with night sights, which enhance visibility in low-light conditions. The combination of these features makes the Sig P320 M17 and M18 highly accurate and effective pistols.

Durability and Maintenance

The Sig P320 M17 and M18 are both highly durable and require minimal maintenance. Both pistols feature a stainless steel slide and a polymer grip module, which are designed to withstand wear and tear. The pistols are also designed for easy disassembly and cleaning, which makes maintenance a breeze. Overall, the Sig P320 M17 and M18 are highly reliable and durable pistols that require minimal maintenance.

Safety Features

The Sig P320 M17 and M18 both feature a number of safety features that make them safe and reliable pistols. Both pistols feature an ambidextrous safety selector, which allows for easy operation for both left- and right-handed shooters. Additionally, both pistols feature a manual safety, which provides an extra layer of safety when handling the pistol. The trigger on both pistols is also designed to provide a smooth and consistent pull, which enhances control and accuracy. Overall, the Sig P320 M17 and M18 are highly reliable and safe pistols that are designed for easy operation and maximum control.

Comparative Analysis

M17 vs M18 Specifications

The Sig P320 M17 and M18 are both full-size handguns that are striker-fired and chambered in 9mm. The M17 is the military version of the P320, while the M18 is the compact version. The M17 has a 17-round capacity, while the M18 has a 21-round capacity.

In terms of weight, the M17 weighs 29.6 ounces, while the M18 weighs 28.1 ounces. The length of the M17 is 8 inches, while the M18 is 7.2 inches long. The height of the M17 is 5.5 inches, while the M18 is 5.5 inches tall. Finally, the width of the M17 is 1.3 inches, while the M18 is 1.3 inches wide.


SIG P320 M18 Holster

SIG P320 M17 Holster 


Concealed Carry Considerations

When it comes to concealed carry, the M18 is the better option due to its smaller size and lighter weight. However, the M17 can still be carried concealed with the right holster and clothing. It is important to note that both the M17 and M18 are full-size handguns, so they may not be the best option for those who prioritize concealment over firepower.

Military and Law Enforcement Use

The M17 and M18 have both been adopted by various military and law enforcement agencies. The M17 was adopted by the U.S. Army as its new service pistol in 2017, while the M18 was adopted by the U.S. Marine Corps and U.S. Air Force as their new service pistol in 2019.

Both pistols have proven to be reliable and accurate in testing and real-world use. They feature a modular design that allows for easy customization and maintenance. The M17 and M18 are also compatible with a variety of accessories and holsters, making them versatile options for military and law enforcement use.

Accessories and Customization

When it comes to accessories and customization for the Sig P320 M17 and M18, there are a variety of options available to you. In this section, we'll take a closer look at some of the most popular accessories and customizations for these firearms.

Optics and Sights

One of the most popular accessories for the Sig P320 M17 and M18 is an optic or sight. Both models come with a SIGLITE night sight front sight and a removable night sight rear plate, which allows you to easily install an optic or sight of your choice.

Some popular options for optics and sights include the Romeo1 Pro and the Leupold Delta Point Pro. Both of these optics are designed to be durable and reliable, and they offer excellent accuracy and precision.

Magazines and Calibers

Another area where you can customize your Sig P320 M17 or M18 is with magazines and calibers. Both models come with 17-round magazines, but you can also purchase 21-round magazines if you prefer.

In terms of calibers, the Sig P320 M17 and M18 are both centerfire handguns that are available in 9mm. However, you can also purchase conversion kits that allow you to switch to other calibers, such as .40 S&W or .357 SIG.

Aftermarket Support

Finally, one of the best things about the Sig P320 M17 and M18 is the level of aftermarket support that is available. There are a wide variety of companies that produce accessories and customization options for these firearms, including grip modules, triggers, and more.

Some popular companies that offer aftermarket support for the Sig P320 M17 and M18 include Apex Tactical Specialties, Grayguns, and Wilson Combat. Whether you're looking to improve your accuracy, enhance your grip, or just make your firearm look more unique, there are plenty of options available to you.

Frequently Asked Questions

What are the primary differences in features between the M17 and M18 models?

The primary differences between the M17 and M18 models are the size and the grip modules. The M17 has a full-size grip module, while the M18 has a compact grip module. Additionally, the M18 comes with a manual safety, while the M17 does not. The M17 and M18 both have a modular design, which allows for easy customization and flexibility.

Is the M18 compatible with the same holsters designed for the M17?

Yes, the M18 is compatible with the same holsters designed for the M17. The M18 has the same slide and barrel length as the M17, and the grip module is the only difference between the two models. As long as the holster is designed to fit the M17, it should fit the M18 as well.

Can the M18 accommodate a red dot sight, and if so, which models are recommended?

Yes, the M18 can accommodate a red dot sight. The M18 has a removable rear sight plate that can be replaced with a mounting plate for a red dot sight. The recommended red dot sights for the M18 are the Trijicon RMR, Leupold DeltaPoint Pro, and Sig Sauer Romeo1.

How does the civilian version of the M18 differ from the military version?

The civilian version of the M18 is nearly identical to the military version, with a few minor differences. The civilian version has a manual safety, while the military version does not. Additionally, the civilian version has a different serial number prefix than the military version.

What are the legal considerations for owning an M18 in states with strict gun laws like California?

In states with strict gun laws like California, owning an M18 may require additional permits and registrations. It is important to research the specific laws and regulations in your state before purchasing an M18. Additionally, it is important to ensure that the M18 is compliant with all state and federal laws.

In terms of size and capacity, how does the M18 compare to the Glock 19x?

The M18 and the Glock 19x are similar in size and capacity. The M18 has a 17-round magazine capacity, while the Glock 19x has a 19-round magazine capacity. However, the M18 has a slightly shorter overall length and barrel length than the Glock 19x. Ultimately, the choice between the two models comes down to personal preference and intended use.

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