Gen 3 is an abbreviated way to convey that a product is in its third generation and has undergone two revisions since its initial introduction.

In our world—the world of firearms—when somebody says Gen 3 they are almost always referencing the Glock pistol. Glock has seen Gen 2, Gen 3, Gen 4 and Gen 5. And now, there’s the V iteration that has recently come to market.

Thanks to the incredible popularity of the Glock pistol, the term Gen 3 is synonymous with Glocks—more so than any other platform—firearm or optic—our industry has produced.

It’s an enviable position to be in.

But it is an issue of concern. No, not for Glock. Glock designed its Gen 3 models, manufactured them, services them, and pretty much dominated sales with them for many years.

The issue arises when others use the term Gen 3 to describe their product as compatible—or cross-compatible—with a Glock pistol or OEM Glock Gen 3 components.

Aftermarket parts makers—and often those selling those parts—adopt the Gen 3 nomenclature to market their products to Glock owners. The same is true for firearms makers that have rolled out clones of Gen 3 models. More than a few have described their pistol as a Gen 3-like pistol.

A good friend had one such pistol—from a maker whose name was not Glock—and confidently declared that it was a Gen 3-based model and thus Gen 3 parts would work in it.

Spoiler Alert: He had issues.

Here’s where the problem lies. Glock makes the Gen 3. Only Glock knows what the exact specs are for the Gen 3. They know all the tolerances. They alone know the QC process to confirm which parts are in spec and which are not.

Everybody else? Not even close.

The aftermarket parts non-compatibility issue popped up once again, this time documented in a video and posted on LinkedIn by Hannah Hannah, who also goes by The Tactical Stylist.

You can see the post here—though I’d ignore the comments unless you enjoy reading endless opinions on what she did wrong from men who carry a gun, shoot a gun, own a gun, have seen a gun in a movie, or have ever used the word gun in conversation.

What happened was that her gun had an uncommanded discharge while reholstering during practice. Insert your own hackneyed P320 joke here, but this wasn’t one of their guns. It also wasn’t a Glock.

The pistol in question is a Shadow Systems MR920. But that’s not the issue, either. The pistol was outfitted with a Timney trigger—and even that, in and of itself, wasn’t the issue. The issue is that the Timney trigger isn’t designed to work in the MR920 but was installed anyway.

Due to wear and the incompatibility of the Timney Trigger in the Shadow Systems MR920, the trigger mechanism broke, resulting in a catastrophic failure of the pistol discharging. Now the striker releases when the trigger resets.

Hannah reached out to Timney after her gunsmith diagnosed the issue and showed where the breakage occurred.

In the video, Hannah shares her positive experience with Timney. In an email back to her, Timney’s customer service explained that ‘although Shadow Systems pistols are based on the Glock Gen 3 platform, the sear housing at the rear of the frame is proprietary to Shadow Systems.’

Timney further explains: ‘Our sear housing is engineered to fit and function only with OEM Glock components. While some users have found creative workarounds to make our trigger operate in a Shadow Systems pistol, that’s not its intended application.’

You can read the full text, which she posted in the description of the posted video.

As for how the Timney trigger kit found its way into her MR920, it’s the ole Gen 3 stamp of approval. If you use the term Gen 3, it automatically means it works. That’s what she experienced when she was told the Timney Gen 3 trigger kit would work in the Shadow Systems MR920 because it’s designed after the Gen 3 Glock.

She shares her story—as embarrassing as it might be—as an important lesson for others. Just because the person on the other side of the gun counter says the magic phrase Gen 3 doesn’t make it so.

Only Glock guns and factory parts are Gen 3. Everything else is pretty close at best—and maybe close at worst.

No matter how much you like a particular gun or component marketed as Gen 3 compatible, you have no clue what specs the manufacturer designed around. You don’t even know if they have actual engineers doing the designing.

And more importantly, you don’t know how well they QC their parts—or even if they do any QC.

The size of the Glock market fostered one of the largest aftermarket ecosystems in the firearms industry. It generates a lot of revenue, and it doesn’t take much to enter that aftermarket beyond a checkbook and somebody to sell you their machined parts under your label.

The next time somebody tells you their product is Gen 3 or fits Gen 3 clone pistols, heed Hannah’s advice and do some research. You might not be as fortunate as Hannah was and walk off the range unscathed when you find out your Gen 3 isn’t Gen 3 at all.

– Paul Erhardt, Managing Editor, the Outdoor Wire Digital Network