The Sig Sauer P320 series is undoubtedly one of the most popular and successful handgun platforms in recent years. Known for its modularity, accuracy, and reliability, the P320 has become a favorite for law enforcement, military, and civilian shooters alike. Among the various models in the P320 lineup, two models have risen to prominence – the Sig P320 M17 and the Sig P320 M18. Both of these guns are adaptations of the MHS (Modular Handgun System), which was adopted by the United States Military as the official sidearm in 2017 to replace the Beretta M9.
In this blog post, we will thoroughly analyze and compare every aspect of these two remarkable handguns – the Sig P320 M17 and the Sig P320 M18. We will cover their features, performance, design differences, as well as their pros and cons to help you make an informed decision on which gun is the best for you.
Sig P320 M17 Overview
The Sig P320 M17 is the full-sized model and is the civilian variant of the military’s M17. The M17 features a coyote tan stainless steel slide, a coyote polymer grip module, a manual safety, and night sights.
Features and Specifications:
- Chambered in 9mm
- Barrel length: 4.7 inches
- Overall length: 8 inches
- Weight: 29.6 ounces
- Capacity: 17+1 rounds (with standard magazine)
- Manual safety and loaded chamber indicator
- Optic-ready slide cut for Leupold DeltaPoint Pro
- Night sights
- Modular design
- 17 and 21-round extended magazines available
Sig P320 M18 Overview
On the other hand, the Sig P320 M18 is the compact version of the M17, sharing a majority of its features and specifications, with some minor differences in size and capacity. The M18 also has a short accessory rail under the dust cover, which allows for the attachment of various tactical devices such as lights and lasers.
Features and Specifications:
- Chambered in 9mm
- Barrel length: 3.9 inches
- Overall length: 7.2 inches
- Weight: 28.1 ounces
- Capacity: 17+1 (with standard magazine)
- Manual safety and loaded chamber indicator
- Optic-ready slide cut for Leupold DeltaPoint Pro
- Night sights
- Modular design
- 17 and 21-round extended magazines available
Comparing the Sig P320 M17 and M18
Size & Weight
The most noticeable difference between the M17 and M18 is their size. The M17 is the full-sized model, while the M18 is the compact. The M17 has a slightly longer barrel (4.7 inches) compared to the M18’s barrel (3.9 inches). The overall length of the M17 is 8 inches, while the M18 has a smaller overall length of 7.2 inches.
As a result, the M17 is slightly heavier at 29.6 ounces compared to the M18’s 28.1 ounces. The difference in weight might not seem like much, but for those who carry their firearms daily, even a small reduction in weight can be beneficial.
Magazine Capacity & Grip Size
Both the M17 and M18 have the same standard magazine capacity of 17+1 rounds. However, the M17 has a larger grip size, which can accommodate a 21-round extended magazine. The M18 can also accept 21-round magazines, but the grip will extend beyond the magazine for a slightly less snug fit.
Individual preference will play a role in determining which model is best suited for your needs. If you prefer a larger grip for better control, the M17 might be the better choice. If concealability and ease of carry are more important, the M18’s smaller grip size can be advantageous.
Optics Compatibility
Both the M17 and M18 come with optic-ready slides cut for the Leupold DeltaPoint Pro red dot sight, allowing users to quickly and easily mount their preferred optic for improved target acquisition and accuracy. Additionally, both models feature night sights, making them suitable for low-light situations.
Manual Safety
A unique feature of both the M17 and M18 is the inclusion of a manual safety, a somewhat rare feature in striker-fired pistols. This makes them particularly appealing to shooters who prefer the added control and safety of a manual safety lever.
Accuracy & Recoil Management
The longer barrel and slide of the M17 can potentially provide a slightly longer sight radius, which may make it easier for some shooters to achieve improved accuracy. Additionally, the larger frame and added weight of the M17 can help to manage the recoil for a more pleasant shooting experience, particularly for less experienced shooters.
Conversely, the M18’s shorter barrel and lighter weight can make concealment and daily carry more comfortable, but may result in slightly more perceived recoil. However, most shooters report that the recoil of the M18 is still quite manageable.
| Feature | Sig P320 M17 | Sig P320 M18 |
|---|---|---|
| Size | Full-size | Compact |
| Barrel Length | 4.7 inches | 3.9 inches |
| Overall Length | 8 inches | 7.2 inches |
| Weight | 29.6 ounces | 28.1 ounces |
| Capacity | 17+1 (Standard), 21 (Optional) | 17+1 (Standard), 21 (Optional) |
| Optics Compatibility | Leupold DeltaPoint Pro | Leupold DeltaPoint Pro |
| Manual Safety | Yes | Yes |
| Recoil Management | Better due to larger size and weight | Manageable but may be slightly more than M17 due to lighter weight |
Which Model is Right for You?
Deciding between the Sig P320 M17 and M18 ultimately comes down to personal preference and intended use. The M17’s larger frame size and increased capacity make it an excellent choice for range use, home defense, and those who prefer a larger grip for better control. On the other hand, the M18’s compact size, lighter weight, and shorter grip make it an ideal choice for concealed carry or those who have smaller hands and require a better fit.
Both models offer excellent accuracy, reliability, and modularity that the P320 series is known for, along with optic compatibility and a manual safety. No matter which model you choose, you’ll be getting a durable, high-quality handgun that has been proven by military and civilian shooters alike.
Frequently Asked Questions
What is the difference between Sig P320 M17 and M18?
The main difference between the Sig P320 M17 and M18 is that the M17 was designed for the US Army, while the M18 was designed for the US Marine Corps. The M17 has a longer slide and barrel, while the M18 has a shorter slide and barrel. The M17 also has a coyote-tan grip module, while the M18 has a black grip module.
What is the difference between the SIG P320 and the M17?
The SIG P320 is the civilian version of the M17, with a few differences in design. The M17 has a manual safety and a reduced-mass trigger, while the P320 does not have a manual safety and has a standard trigger. The M17 also has a coyote-tan grip module, while the P320 has various color options for the grip module.
Does Army use M17 or M18?
The US Army adopted the Sig P320 M17 as its standard sidearm in 2017. The M18 was then adopted by the US Marine Corps in 2019. Both models are currently in use by the military.
What is the SIG M18 equivalent to?
The SIG M18 is essentially the same as the civilian P320-M18, with a few minor differences in design, such as a manual safety and reduced-mass trigger. However, the M18 was specifically designed for the US Marine Corps and features a few modifications requested by the Marines, such as a shorter slide and barrel for easier handling in close-quarters combat.
What is the size and weight of the SIG P320 M17 and M18?
The Sig P320 M17 has a slide length of 4.7 inches, overall length of 8 inches, height of 5.5 inches, and weighs 29.6 ounces. The Sig P320 M18 has a slide length of 3.9 inches, overall length of 7.2 inches, height of 5.5 inches, and weighs 28.1 ounces.
What is the magazine capacity of the SIG P320 M17 and M18?
The Sig P320 M17 and M18 both have a standard magazine capacity of 17 rounds, with an optional extended magazine capacity of 21 rounds.
Are the Sig P320 M17 and M18 modular?
Yes, both the Sig P320 M17 and M18 are modular handguns, meaning that the internal chassis or “fire control unit” can be removed and placed into different grip modules. This allows for customization of the grip size, color, and texture.
What is the price difference between the Sig P320 M17 and M18?
As of 2021, the Sig P320 M17 has a starting price of around $600, while the Sig P320 M18 has a starting price of around $700. However, prices may vary depending on where you purchase the firearms.
Are the Sig P320 M17 and M18 reliable?
Yes, both the Sig P320 M17 and M18 are known for their reliability and have passed rigorous testing by the US military. The handguns have also received positive reviews from civilian gun owners and firearms experts.
What type of ammunition does the Sig P320 M17 and M18 use?
The Sig P320 M17 and M18 use 9mm ammunition, which is a popular and widely available caliber for handguns.