Review: Sig Sauer P320 Sub-Compact X-Change Kit

We just reviewed the excellent Sig P320 compact in 9mm and absolutely loved it. The compact frame in the medium size fit into my hand like it was designed for it. I wanted to know if the sub-compact version would feel just as at home as the compact. The X-Change kit that we requested was the 9mm with the small frame, a mistake that I would later realize.

WARNING: Industry professional rant incoming! 

The X-Change kit showed up in a plastic case that resembled a smaller version of the Sig pistol cases that we are all familiar with but it was wrapped in a strange cardboard wrapper with a hole in it for a peg hook. I am not sure why Sig designed the packaging to be hung on a peg, it seems like this isn’t the sort of thing you hang next to spare mags and cleaning kits. After working in the shooting sports industry I have become reasonably familiar with how often customers will buy something when they thought it was something completely different, I sure would hate to think of the customer complaints when they bought what they thought was a gun only to find a few crucial components missing.

Rant over, continue about your normal activities. IMG_3072 IMG_3201

Related: SIG P320 Selected as new US Army Handgun.

The P320 comes apart rather easily to swap the pistol to the sub-compact configuration. I was able to take the compact apart and reconfigure it in about 2 minutes. Included in the kit is a complete slide with the standard Siglite night sights, a barrel in the respective caliber, a guide rod and recoil spring assembly, one magazine and the grip frame in your choice of sizes.IMG_3194

All put together the pistol looks pretty fantastic for a plastic wonder 9. The forward serrations on the pistol are a nice touch, I like that the pistol retains most of the functionality of the larger gun with the exception of the mounting rail. My understanding is the rail is still on the larger frame sizes starting with the medium on up.  IMG_3174 IMG_3175

Previously I stated that I regretted the choice on the frame size, there is one thing that I found rather annoying about the small frame. The slide stop protrudes quite a lot on the smallest frame, I am sure this is necessary so that the frame fits in as many grip frames as it does. It did cause one of my friends that went with me to test the sub-compact experienced the slide locking back mid magazine every now and again thanks to his grip on the pistol. The slide lock failures were the only malfunctions that anyone had experienced in about 1400 rounds of testing the P320 with the exception of a upside down limp wrist test that just about every handgun will reliably fail.    IMG_3178 IMG_3180

The standard night sights on the pistol were a really wonderful touch, I really like seeing that they include upgraded sights straight from the factory. IMG_3183 IMG_3184

Included in the sub-compact X-Change kit is one magazine in the correct size, I would have liked to see two even if it bumped the price up a touch. I can understand Sig omitting a second mag in the effort to keep the price low and within reason. Capacity on the 9mm subcompact is 12 rounds, about on par with other pistols of the same size. IMG_3187

Getting out to the range with the P320 and the sub-compact X-Change kit was something I had been looking forward to all week. Once out there I quickly found that while I had fallen in love with the compact P320, the smaller frame just didn’t agree with my hands. I was still able to shoot it quite well and would probably seriously consider it as a carry gun with the medium frame instead of the small, after all the P320 is fantastic and would be a really solid choice. The recoil was as one might expect with a small handgun but it wasn’t anywhere near uncomfortable of difficult to control.   1 2

From about 7 yards I did a bit worse than I did with the compact on a previous range trip, it was still a pretty respectable group for a sub-compact though. IMG_3086

Overall I have been nothing short of impressed with the P320 in the sub-compact size, I definitely give it a thumbs up. The X-Change kit is a great idea for shooters that aren’t able to purchase more handguns as a result of legal loop holes as well as those that don’t care to buy more than one. When I was a freshly married man in my early twenties I would have killed for a pistol like the P320 since I didn’t have much money at the time, the ability to pick up the capability of another gun for about half price would have been game changing for me.

The P320 X-Change kit carries a MSRP of $399 with a street price closer to the low 300 dollar mark. If you would like to learn more about the converion kits you can check them out on the Sig Sauer website by clicking HERE.

Patrick R

Patrick is a Senior Writer for The Firearm Blog and TFBTV Host. He likes guns and has liked shooting guns for as long as he can remember. You can follow Patrick on Instagram @tfbpatrick, Facebook, or contact him by email at

The above post is my opinion and does not reflect the views of any company or organization.


  • Richard

    The gun store in Tampa that I went to had the kits on a kiosk looking thing in the middle of the tactical section

  • Joe

    I carry the compact slide on top of a subcompact frame. Feels a little top heavy, but I don’t seem to notice when I’m shooting. It gives me pretty good capacity and the grip is easy to conceal. All for the cost of $80 ($40 grip and $40 mag).

    • Jeremy Star

      Yup, compact slide on sub grip seems to be the way to go. WAY cheaper than the whole exchange kit. Now, if they would just get the medium sub grips in stock so I could order one…

      • nova3930

        SC medium is what I went with. allows for holster compatibility between the 320C and the 320SC config

  • Gary Kirk

    Now I just need the review of the full size in .357 sig.. Oh, with threaded barrel

    • Ed McRight

      Have the p250 compact and subcompact in 357sig. Much better Ballastics with little felt recoil over 9mm. It doesn’t have the flip of the 40. Won’t have threaded barrel till I don’t need a tax stamp.

      • Gary Kirk

        I was leaning more towards a compensator on the full size.. Until I can get a can.. The compact and sub compact don’t have any need for a threaded barrel in my opinion

  • Kelly Jackson

    When you see the sub compact in photos the grip looks like it’s silly small but it practice it actually fits your hand unlock that Lego block Glock grip

  • Kelly Jackson

    Personally I like the sub compact P250 frame with the rail more. I think it looks better and it’s more handy. I know they swap with the P320 action but they seem increasingly harder to find.

    • nova3930

      The SC medium frames with the rail are around, just not as numerous as the other flavors. I went with a medium to drop my 320C slide on for holster compatibility

    • Medium and large subcompact grip modules should have the rail. They are available from retailers, but he easiest place to buy it is direct from SIG.

  • Scott

    The railed version of the 9mm subcompact is the 320-SCR-9-B or BSS. Interestingly, the SCR version comes w/ the medium grip module, but the SC version w/ out the rail comes with the small grip module, and is the only 320 not to ship w/ the medium module.

  • My usual preface: I am a member of Team SIG, and am provided a SIG P320 for competition shooting.

    “The X-Change kit showed up in a plastic case that resembled a smaller
    version of the Sig pistol cases that we are all familiar with but it was
    wrapped in a strange cardboard wrapper with a hole in it for a peg
    hook. I am not sure why Sig designed the packaging to be hung on a peg…”

    Within SIG’s Store within a Store concept the X-Change kits are on racks in the middle of the section with the rest of the accessories. That is why it has a peg hook.

    “The slide stop protrudes quite a lot on the smallest frame…”

    I haven’t handled every single grip module (though I have the others sizes I don’t use on the way), but that section of the grip module. I am told is the same size across all the models/sizes.

    • Gary Kirk

      Ok, you’re team Sig.. So maybe you’ll be able to answer my question.. Have you had a chance to try the 320 full-size in .357? I am very interested in this firearm, and am honestly looking for some user input..

      • Sorry, I’ve only shot the 320 in 40S&W and 9mm. I can say that it handles major PF 40S&W loads quite well.

        • Gary Kirk

          That’ll work.. I know, I’m a bit of an odd ball with the.357 fetish.. Have a couple 40s that don’t hesitate to do their job. And am in the process of getting the barrel to convert my 96FS to.357.. But want something that I can easily change calibers, grip size, slide size… So the 320 has me, I have always had a soft spot for Sig, was gonna reserve my next pistol purchase for a 226 tac.. But may have to reconsider

  • that_guy

    Whats up with the support-finger-on-trigger-guard?

    • Patrick R. – Staff Writer

      Because that is where I like it.

    • BrandonAKsALot

      That’s how I shoot. It feels more secure for me.

      • that_guy

        If that’s how you shoot comfortably and are able to hit your target then all power to you. I’ve just never been taught like that in any course I’ve taken nor seen any of the big timers shoot like that…That’s why I asked.

        • BrandonAKsALot

          Most of my pistols are concave and serrated on the front of the trigger guard, so I kind of assumed that’s the reason and it was somewhat common. I like it because I feel I get a more solid hold and a little less muzzle rise. To each their own.

  • i1776

    Thanks for the links in the article that go to click bait sites like Ebay and Cabelas. I needed that.

  • Dave D

    Noticed that the pictures show the new style slide stop on the old style grip module. The new style is slimmer and the new grip modules are formed around the small slide stop. Can only think that may have helped with the accidental slide stop engagement.