With the Amend2 S300 Grip Module, You Can Use P365 Mags in Your P320!

Much like everyone else in our consumer-driven world, I love new things! Especially when they are affordable. The S300 Grip Module from Amend2 happens to be both new and affordable. Amend2 is mostly known for its magazines made for AR 15s, AR 10s, and Glocks. The S300 came out of nowhere and premiered at SHOT Show 2020. Then we got a long wait between then, and the time the S300 hit the American market.

Obviously, since March 2020, things have been a bit crazy, and everything hit a delay or two. Luckily, the S300 grip modules are here and ready to take your P320 to the next level of concealment.

I ordered mine ASAP and have been putting lead downrange all weekend long.

So What’s the S300 Do?

The S300 is a P320 grip modular that allows you to shrink your P320 beyond subcompact. In fact, it shrinks the grip considerably, so much so that P320 magazines are no longer an option. Instead, the S300 grip module utilizes Sig P365 magazines. This crazy hybrid design uses the P320 FCU combined with P365 magazines to provides the smallest P320 possible.

Amend2 s300 P320 grip with P365 magazine
This hybrid grip module makes a big gun quite small.

Remember how the Glock 19X used a long grip with a shorter slide? Well, the S300 does the opposite. You get a shorter grip with a long slide which sounds odd but presents a rather effective concealed carry firearm.

Why Would I Want That?

Good question, and maybe you don’t want it. I can tell you why I wanted it, though. First, it makes for a much more concealable gun at a very small price point. If you already own a P365, then it might not make much sense for you. However, if you have a P320 and want something smaller for concealed carry, a 59.99 grip module is much cheaper than a 500 dollar Sig P365.

Sig P365 and P320 with Amend2 s300 grip module - both guns with P365 magazines
Now these two share magazines.

At the same time, the Sig P365 magazines are quite common and vary widely in capacity from 10 to 15 rounds. The S300 grip module follows the standard P365 length and allows for the use of flush-fitting 10 round magazines or the extended 12 and 15 round magazines. For IWB fit, the smaller grip makes the weapon easier to conceal. The longer barrel and slide don’t much matter for concealed carry in an IWB configuration.

The S300 provides a super-short grip making the weapon extremely concealable. The longer slide and barrel have their own benefits when it comes to control, accuracy, and features. The P320 slide allows you to utilize a full-sized red dot sight, as I have with the SIG ROMEO1PRO. Additionally, the S300 packs an actual Picatinny rail over the P365’s silly proprietary rail.

Picatinny rail on Amend2 s300 grip module for P320
The Picatinny rail makes adding accessories quite easy.

Now you might be saying, well hell, now I need a new holster! Nope, you actually don’t need a new holster. The S300 grip module allows you to keep your P320 holster and provides zero issues with most holsters.

Does the S300 Work?

Installing the fire control unit (FCU) from your P320 to the S300 grip module takes almost no effort. Just Pop out the pin, pop it into the grip module, reapply the pin and call it a day. The fit is perfect, and the FCU slides into the module without any issues. Once installed, you drop your slide on and slap a P365 magazine in place, and you are ready to go.

Travis Pike aiming a P320 with an Amend2 s300 grip module and Sig ROMEOPRO red dot sight
The S300 allows me to use full-sized red dot optics.

The S300 grip module mimics the P365’s grip texture almost perfectly. It’s an aggressive little grip that is most certainly necessary for the teeny tiny grip. The grip is very, very small, and only with the 12 round magazine do I have what I describe as a full grip. With the ten-rounder in place, I got a major case of the hanging pinky.

Travis Pike shooting the P320 fitted with the Amend2 s300 grip module. Image demonstrates his ability to maintain control even though the grip is small.
I managed to retain control even with the super small grip.

Also, the ten rounder has a very soft click when you insert the magazine, and I always gave it a little tug to make sure it’s really in there. The 12 and 15 rounders gave a much more satisfying click when installed.

After everything sat in place, I loaded up my P365 magazines with 147-grain 9mm and hit the range. I wanted some spicy rounds to see if the super smaller grip made it tough to control the short little grip module.

Amend2 s300 grip module on P320
The texture of the grip almost matches the P365 perfectly.

To my surprise, the S300 remained plenty easy to handle and control. Well, more so with the 12 and 15 round magazines. The hanging pinky didn’t help, and I didn’t feel like I had the max control over the gun with the flush-fitting magazine. The 12 rounder balanced the small size of the frame with max control well. The 15 rounder gave me the exact same capacity as the P320C with the smaller frame as well.

Does It Affect Reliability?

Reliability is a pretty big issue with a concealed carry pistol. Concerns regarding a third-party company producing a grip module that mixes one gun’s slide with another magazine seem like it could quickly create issues. If it does, I haven’t found them just yet.

shooting the P320 with Amend2 s300 grip
The S300 and the P320C made a very competent concealed firearm with lots of full-size goodies.

Outside of the 147-grain loads I fired, I went through some plain jane 115-grain loads, some steel case Winchester Forged ammo, and some 124 grain SIG +P JHPs. I ran into zero issues in terms of basic reliability with the S300.

Sig P320 with the Amend2 s300 grip module and a 10, 12, and 15-round magazine.
The P365 offers a multitude of carry and capacity options.

Accuracy was still fantastic. The Legion series trigger with the SIG ROMEO1PRO made it so damn easy to ring tiny gongs offhand. At 25 yards, I made that four-inch gong swing and swing and swing. I cycled through my smallest steel targets and never had an issue engaging them with both speed and accuracy.

Hitting the Reload Button

Reloads are tricky, at least for me. My big hands pin the magazines in, and I have to do this crazy open-hand maneuver to get the magazines to drop free. However, they do drop free when my 2XL hands aren’t in the way. The teeny tiny grip does make reload trickier.

Sig p320 with s300 grip, P365 magazine and ROMEOPRO1 red dot sight
10 to 15 round magazines offer you varying capacities.

That being said, the S300 grip module retains the ergonomics of the P320. This includes the ambi slide stop and larger magazine release. The S300 has some of the weaknesses of a smaller grip but does a great job of giving you the strengths of a larger gun.

P320 hybrid concealed carry gun next to P365
The hybrid gives you the right sized weapon for concealed carry.

Saddling Up

The S300 grip module is an interesting piece of gear. It checks lots of boxes for me. It’s super handy, keeps the gun reliable, and makes it much smaller and easier to conceal. I love having the smaller grip module with a full-sized red dot and my favorite striker-fired trigger. Plus, it’s American-made from a small business, and it’s affordable. It’s a winning combination of features, and I think it’s a great buy for P320 owners who want to deep conceal their pistol.