In 201
4, Sig Sauer introduced its first striker-fired polymer semi-automatic pistol, the Sig P320. It is available in full size and carry models and I want to review them and offer my comments to help you decide if they meet your purposes and preferences. They are a modular, striker-fired handgun with several options and features to easily customize and configure for different uses. Incidentally, Sig Sauer did not pay me nor provide free handguns or ammo for this review.Sig has long been known for their quality, double-action, traditional all-metal hammer-fired pistols. Over the years, striker-fired polymer pistols have been in the spotlight, especially for law enforcement agencies, with Smith and Wesson M&P, Glock, and Springfield striker-fired polymers. Of course, there are some who do not desire the striker-fired pistols and do not want polymer ones, but that is a personal preference for each to decide.
Here are the Specifications for the two new Sig P320 Models in 9mm:
SIG P320 Carry
- Action: Striker-Fired Double Action Only
- Caliber: 9mm, .357 SIG or .40 S&W
- Barrel length: 3.9”
- Capacity: 15 rounds (9mm), 13 rounds (.357 Sig and .40 S&W) (2 metallic mags)
- Trigger pull: 5.5 to 7.5 pounds
- Sights: SIGLITE night sights
- (no external safety or decocker)
- Frame: Stainless steel
- Grips: Interchangeable polymer grip module frame
- Finish: black matte Nitron
- Accessory Rail: Yes
- Overall length: 7.2”
- Overall height: 5.3”
- Width: 1.4″
- Sight radius: 5.8”
- Weight: 26 ounces (with magazine)
- MSRP: $669.- 713. (lower street price available)
SIG P320 Full Size
- Action: Striker-Fired Double Action Only
- Caliber: 9mm, .357 SIG or .40 S&W
- Barrel length: 4.7”
- Capacity: 17 rounds (9mm), 14 rounds (.357 Sig and .40 S&W) (2 metallic mags)
- Trigger pull: 5.5 to 7.5 pounds
- Sights: SIGLITE night sights
- (no external safety or decocker)
- Frame: Stainless steel
- Grips: Interchangeable polymer grip module frame
- Finish: black matte Nitron
- Accessory Rail: Yes, full-length Picatinny
- Overall length: 8”
- Overall height: 5.5”
- Width: 1.4″
- Sight radius: 6.6”
- Weight: 29.4 ounces (with magazine)
- MSRP: $669.- 713. (lower street price available)
Modularity & Interchangeability Features

Sig has developed a nice modular 320 pistol with interchangeable features, although not a new idea. The Sig P250 was a modular design and some have concerns with the older models, but the 320 is a very different design. In my opinion, with the P320 design they have developed a very good modular pistol with an easy, quick, versatile, and efficient way to change grip sizes, frames, slides/barrels, and calibers for different purposes. Should be an easy caliber switch by changing a serialized part, no FFL, and I understand conversion kits are becoming available.
The modular grip frame assemblies (in small, medium, & large frames) and removable fire control (serial-numbered trigger) assembly unit make them easily convertible and to any size hand and use. Rather than interchangeable back-strap panels, Sig decided to offer interchangeable grip frame assemblies (non-FFL part.) The modular grip frame assemblies are one whole unit and can be purchased separately for less than $50 each. So if you mess up your frame or your grip stippling efforts for the gun, you can just replace the grips/frame easily and for a low cost, as another advantage. Although, the grip and its medium stippling texture (without being too aggressive) feel great to me as they are. The assemblies are offered for both the full size and carry models.
The 320 design allows you to convert between a carry and full size pistol. I was really amazed at how easily this non-mechanical guy was able to remove the trigger fire control housing assembly unit and switch modular frames from a large to small one in about 10 seconds, so my wife could better handle her 9mm. I really like this feature and my wife finally found a grip frame that is comfortable with the right ergonomics for her small (but lovely) hand and fingers. The 320 trigger is really then one trigger for all purposes, allowing you to use your perfected and tweaked trigger on different frames, calibers, and 320 guns. We bought both a full size and carry size 320 pistol in 9mm and two modular grip frame assemblies to use for our different purposes and to customize them for our hand sizes, etc. We did add a green fiber optic front sight to my gun for my ancient eyes. So, we don’t have to share the 320 for our frequent, different, and customized uses. By the way, the 320 is offered with two different triggers, the standard and one with an integral trigger blade safety (mostly for law enforcement.) Also you should know that the 320 trigger assembly is designed to fit into the hammer-fired Sig P250 and so some aftermarket parts are available. A friend said the 320 full size takes P250 mags (17 rounders steel with SKU 1300114- $40.), grips, and holsters, although the 320 comes with a decent holster and two metal mags. It also uses P226 sights. Here is the trigger fire control housing assembly unit.

Some Selected Sig 320 Features
- SigLite Nights Sights Included as Standard
- Ambidextrous Slide Stop
- Reversible, Triangular, Raised & Serrated Magazine Release
- Factory Threaded Barrels Available for both Full Size & Carry
- Quick & Safe Take Down with No Tools or Trigger Manipulation
- Magazine must be removed & Slide Locked to Rear for Take Down
- Has Striker Safety, Disconnect Safety, & 3-Point System Safety

Comments After Shooting the 320
To me, the new, modern, and different Sig 320 design, fit, finish, and appearance are excellent. Its quality Nitron finish looks and feels great in the hand, as usual with Sig products. Both models have a stainless steel frame with the matte black Nitron finish and real nice black, contoured polymer grips. There are no external safety or decocking levers to catch or snag when drawing and help with concealed carry. But you cannot judge only by appearance, so what about accuracy, the trigger, how it shoots, and other factors?
I shot about 200 rounds through my 320 full size and found it to feel solid and I could easily handle the recoil, even with the higher bore axis, a minor factor to me. The slide was very easy to rack and it had nice and good looking front and rear side serrations to help. The DAO striker-fired trigger press was somewhat short and medium-light with a quick positive reset, although as expected not nearly as short and light as my 1911s and my other single action guns. The 320 trigger was not gritty or long, with a positive, smooth, and short takeup and decent release. Most striker-fired guns have a heavier (but tolerable) trigger press from the way they are designed with the firing pin reset done by the slide’s cycling action, like my Glocks and Springfields. I put an Apex trigger kit in my Smith & Wesson M&P Pro and it has a real smooth, soft, and short press. The 320 did not have a bad trigger press and it reminded me of my Glock 19, but with a much better press and reset out of the box. The partially pre-tensioned striker helps make a definite reset. However, the 320 press was not as crisp and as soft as I like. After several readings and only 200 rounds fired through it, my Lyman Trigger Pull Gauge gave a press average of about 6.8 pounds. Since the trigger assembly is so easy to remove, I can hope for a modified trigger with a softer press to be released or take it to my gunsmith for trigger tweaking. I can live with the low-to-medium firm and fairly short press for now… especially because my accuracy was decent with it. With the borrowed 320 full size while at the Sig Sauer Academy, I was able to quickly shred the target positioned sideways and easily and often hit center mass at 15 yards or so… a feat for this old timer. Really this 9mm gun is much more accurate than I am. I had no malfunctions or stoppages whatsoever and it was a joy to shoot.
Conclusion
I recommend the new Sig Sauer P320 DAO striker-fired pistols primarily because of their high build quality, accuracy, modularity, conversion and customization options, comfort, solid feel, and overall ergonomics. My only concern was the somewhat heavier trigger press that I am use to with my single-action-only guns. That is just my personal idiosyncrasy and it should not stop you from considering this fine handgun.
Continued Success!
SIG SAUER CONTACT: www.sigsauer.com; Phone: (603) 610-3000
Photos by author.
* This personal opinion article is meant for general information & educational purposes only and the author strongly recommends that you seek counsel from an attorney in your state or jurisdiction for legal advice and your own personal certified weapons trainer for proper guidance about shooting & using YOUR firearms, self-defense, stand your ground law, and concealed carry. This is not legal advice and not legal opinions. It should not be relied upon as accurate for all shooters & the author assumes no responsibility for anyone’s use of the information and shall not be liable for any improper or incorrect use of the information or any damages or injuries incurred whatsoever.
© 2014 Col Benjamin Findley. All Rights Reserved. This article may not be reprinted or reproduced in whole or in part by mechanical means, photocopying, electronic reproduction, scanning, or any other means without prior written permission. For copyright information, contact Col Ben Findley at [email protected].