The S300 Grip Module – Blend your P320 and P365

One grip module to rule them all? Well, one grip to rule at least a couple of SIG models.


Hasn’t SIG been killing it lately? The P365 started a revolution and sold like crazy. The P320 became the Army’s latest service pistol. SIG’s optics, suppressors, and rifles have taken off and gained massive popularity in the police, military, and civilian markets. While the rifles are cool, today we are going to talk about the P320 and P365. Actually, we are talking about how you blend them with the use of the S300 grip module.

The S300 grip module comes from a company called Amend2 which traditionally makes Glock and AR 15 magazines. They premiered this module years ago, and now it’s finally hit the market. The S300 grip module retails for a mere 59.99 and allows you to blend your P320 and P365 with ease. When I say blend, what I mean is that the S300 allows you to use the P320 slides and Fire Control Unit with P365 magazines.

The point of blending the two allows you to shrink the profile of the P320 significantly. It makes the grip of the gun extremely short and compact. Users can drop in 10, 12, or 15 round magazines and effectively match the capacity of the SIG P320 compact. With the 10 and 12 round magazines in place, the S300 grip module is a stealthy beast.

The S300 in the Waistband

Concealed carrying a handgun isn’t easy, but with the right holster, belt, and some common sense, you’ll get it done. If you carry IWB, then the S300 grip module offers you a very easy to conceal gun that’s still a very competent fighting pistol. By shrinking the grip portion, you are shrinking the portion of the gun that’s most difficult to conceal when you carry OWB.

The smaller grip module is easily concealed by nothing more than a t-shirt. Yet, like a great white shark, what sits below the water/waistline is what matters. In your waistband, you have a P320 slide with its longer barrel, larger size, and sights. It brings benefits like being easier to control, easier to shoot accurately, and compatibility with P320 accessories.d

Let me use my S300 created hybrid P320/P365 as an example as to why this is beneficial. On my P320, I have the Legion flat-faced trigger with its incredible trigger pull. Additionally, I can use my SIG ROMEO1PRO, which is a full-sized, duty-grade optic with a massive window. The S300 grip module also offers a full-length Picatinny rail that allows for the mounting of large, powerful lights.

At the same time, the grip module is smaller than the P320 subcompact. I’d rather have a short grip with a longer slide and barrel. This provides me a weapon that’s easy to conceal and easy to shoot.

Going Whole Hog

With my P320 compact slide installed on my S300 grip module, complete with the 12 round magazine, I can have a thin but hand-filling grip that’s still extremely small and easy to conceal. I call it a reverse stretch P320. It looks goofy, but once you hit the ground running, you’ll be surprised at how comfy the gun is to carry and shoot.

I can shoot the S300 equipped P320 much better than I can the P365. The increased weight and longer sight radius make it much easier to shoot quickly and with greater accuracy. With the red dot on top, I can step back to 50 yards and still easily ring steel with the S300 hybrid setup.

I can’t get that kind of accuracy out of the P365. It’s just not happening. While the grip is smaller, I don’t feel a major loss of control. Sure, a bigger grip is nice, but being able to deep conceal a P320 with a TRL-1 and red dot is a very nice touch.

Going Bang

I ran into zero reliability issues with a few hundred rounds. Magazines clicked into place without complaint. However, the ten-round mags delivered a rather soft click, but they always locked in place. The magazines have no issues tripping the slide lock and feed and eject without problems.



The S300 provides a great blend of size and capability. I’m genuinely surprised that SIG didn’t think of it first. It’s such an easy upgrade. Slapping the FCU in the gun and the slide on the gun takes no time at all.

If you want to swap between grip modules, you can do so in about the same time it takes to put on your boots. If you need to swap from normal concealed carry to a deeper concealed carry, you can with the swap of a grip module.

What About Holsters?

Fair question. When you start swapping parts and pieces with guns, you might start to worry about your ability to carry the gun. No one wants to buy another holster just to carry the S300, and the good news is you don’t have to. You can use standard SIG P320 holsters. Obviously, you’ll need the right size depending on your slide, but it’s just that easy.

Being able to use the same holster not only saves you some hard-earned dinero but reduces your training needs. If you can use the same holster, it’s ready and willing to provide you the same service it always has. Now it just carries a slightly smaller gun.

Ultimately the S300 is a unique tool you can put in the box. It provides you an awesome means to customize your SIG and shows just how unique the P320 system is.

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Travis Pike is a former Marine Machine gunner who served with 2nd Bn 2nd Marines for 5 years. He deployed in 2009 to Afghanistan and again in 2011 with the 22nd MEU(SOC) during a record-setting 11 months at sea. Travis has trained with the Romanian Army, the Spanish Marines, the Emirate Marines, and the Afghan National Army.

He serves as an NRA-certified pistol instructor and pursues a variety of firearms-based hobbies.


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