Up Your Glock With the Shield S-15 Magazines

Was I blown away when the Glock 43X and the Glock 48 premiered? No, not really. The Sig P365 had already been out for a year and offered a smaller gun with equal to or greater capacity. I found the 43X and 48 to be a bit underwhelming. Now I would have felt a helluva lot different if Glock kept the thin dimensions of the gun and packed 15 rounds into its flush-fitting magazines, but they didn’t. Glock didn’t anyway – but someone else did. A little company called Shield Arms managed to do it with their S-15 magazines (yes, we carry them, and that’s because some of us reviewed ’em and liked ’em – as you are about to see here).

The S-15 magazines are now in their second generation, and they have been in constant demand since they unveiled the first generation. People love Glock pistols, and the G43X and G48 are both very reliable, easy shooting guns primed to be thin and easy to carry. The 10 round OEM magazines kind of suck in a day and age where Micro-Compacts rule the concealed carry stage.

Shield Arms produced the S-15 2nd Gen to make a few improvements they saw necessary. First, they did ambidextrous magazine release cuts so lefties could be accommodated. The mag catch windows are smaller, which helps reduce the up and down movement of the magazine in the magwell. They also improved the tube and baseplate geometry for a more reliable magazine.

How Did Shield Arms Do This?

Well, they stripped the plastic off the magazines. The Glock OEM magazines utilize a polymer coating like all Glock mags. As we know, for a polymer to be as durable as metal, it has to be a bit thicker. If you trim that polymer coating off of the Glock magazines and make them metal, they are suddenly a little wider on the inside and can accommodate those five extra rounds.

Bam, now you got 50% more ammunition in a flush-fitting magazine. For me, it’s tough to give a crap about the OEM magazines when these are available. Shield Arms made their name producing magazine extensions, which I have and think are excellent.

Glock 43x/48 OEM magazine compared to Shield Arms s-15 magazine — The mags are the same size, but one holds 15 and one holds 10. Also, check out that aggressive baseplate.

Shield Arms even produces +5 magazine extensions for your S-15, so if you want to step it up to 20 rounds, you can. Especially if you carry a spare pocket magazine and want a little more ammunition on the very rare occasion, you’d have to reload.

I approached loading the S-15 magazines with some caution. After loading the Hellcat and P365 15 round magazines, I expected it to be a workout past round 12. I was pleasantly surprised that the S-15 mags were easy to load the whole way through. I never craved a magazine loader to spare my poor hands from the work.

Do the Shield S15 Magazines Work?

Here’s the big question, right? If the S-15 magazines challenge the reliability of the gun, then they are nothing but paperweights. I brought a healthy dose of Winchester White Box and two S-15 magazines to the range over the never several days. With the S-15s fully loaded, I began playing the song of my people.

I ran through a round of good old-fashioned Dot torture, which tests shooters, guns, and gear in a variety of ways. This drill utilizes reloads, drawing, non-dominant shooting, and single-hand shooting. I bulldozed my way through the Dot Torture drill without any issue.

Shield Arms s-15 magazine next to Glock OEM G43x/48 magazine — With 50% more ammunition it’s tough to go back to OEM magazines.

How do you test a magazine other than just shooting it? Well, reload drills, of course. I live on a Florida sandhill, and the white sand will test the hell out of anything related to guns. I dropped the magazines into that white sand over and over again. The S-15 dived into the sand at all angles and ate up a healthy amount of it.

By the end of the first few reloads, the follower gritted along as I loaded round after round into the S-15. Yet, it didn’t stop or fail. I loaded the rounds one by one and unloaded them the fun way one by one. The sand didn’t create any feeding issues.

sand inside of a Shield Arms s-15 magazine — See all that sand? Mags still worked.

In terms of durability, I did dry reloads on my hardwood deck every evening for a week as part of my dry fire practice. They hit and bounced off the ground for what must have been hundreds of reloads as the sun set, and they still function completely fine. No dents, no follower issues, no base plate problems, and no detectable issues that I can find.

Speaking of Reloads

Throughout all these reloads, I came to appreciate the base plates on the S-15 mags. They provide a more aggressive lip than the Glock OEM magazines. To me, this makes reloading easier and more intuitive. It helps me lock onto the magazine and draw it from my pocket clip mag pouch. That baseplate also has a dot matrix that allows you to mark it easily.

Reloading the G48 with Shield Arms s-15 magazine — The big lip makes them easy to reload.

Even after the sand, the on-the-deck reloads, and the hundreds of rounds through the magazines, I’ve yet to experience a failure with them through my Glock 43X. They run and run and run without issue. I heard of problems with the initial Gen 1 S-15 magazines, so I did approach with caution and wanted to ensure my testing was thorough. It seems whatever kinks the Gen 1 mags had have been worked out.

Mag insertion on a closed slide — They insert easily on a closed slide.

The S-15 Downsides

Surely there is no such thing as a free lunch. As metal magazines, these things will start eating up your Glock OEM mag catch. I’ve used them for hundreds of reloads and only see minimal wear, but I’ve already ordered the Shield Arms metal mag catch to replace the OEM model.

Glock 43x with two Shield Arms s-15 magazines — Once you go S-15 you don’t go back.

Not a big big deal, right? Well, sadly, you get Uno reverse carded, and the metal mag catch will wear away at the polymer of the OEM mags. If you choose to use the Shield S-15 magazines, then you will be stuck using just them. To me, it was a worthwhile decision to increase my carry capacity.

Dot matix on the bottom of a Shield Arms s-15 magazine — The dot matrix makes it easy to mark your mags.

Another issue is it might be tougher to find a mag pouch that accommodates the S-15 magazines. Shield Arms makes one, and I use the Neo Mag, which works perfectly with the S-15.

Shield Arms and Glock Magazines

I hope Shield Arms keeps developing this idea of metal magazines in Glock firearms. What if we can get 20 rounds in a Glock 17 flush-fitting magazine? Or 17 in a flush-fitting Glock 19 mag? It might be a worthwhile future for Glock magazines. I think the S-15 magazines for the Glock 43X and Glock 48 are game-changers.

I have a very small and easy-to-carry gun packing a Glock 19’s worth of capacity. What’s not to love? Check ‘em out if you want to up your Glock’s firepower.

One thought on “Up Your Glock With the Shield S-15 Magazines”

Phil Herbert says:

February 2, 2023 at 9:53 am

I have one of those G43X MOS that the Shield Arms S15s just will not work in. I’ve sent my mags and mag catch back to SA only to be told “they’re in spec and function fine.” I have an untouched OEM G43X and my 3 Shield Arms S15s continually fail to feed (FTF) and fail to extract (FTE). The S15 fit is sloppy in my mag well as the S15s move around with ease, while the OEM Glock mags fit snug.
At Shot Show 2023 Brendan Z from Shield Arms introduced the Gen3 S15, which has 2 dimples on the back of the magazine tube to address that sloppy play at the top of the mag well. I’m working on getting my hands on a couple to test fire since my gun is one of those anomalies.