Why won’t the website let me order a threaded barrel?

Most likely because you’re trying to ship it to California. California prohibits the sale of threaded barrels and expressly forbids retailers to ship threaded barrels into the state. We like staying in business and not getting sued out of existence, so don’t get mad at us. Thank your local lawmakers and fellow voters for electing them.

What are maritime spring cups?

Maritime Spring Cups were designed to accommodate a request by a special operations military group who was concerned about the ability to fire their Glock pistols after they had been submerged underwater. The ports in the Maritime Spring Cups were engineered to allow water and debris to empty out of the firing pin channel, preventing malfunctions.

While this might seem beneficial, the ability for more foreign substances to come out also means that more foreign debris can come in.

The fact is, you can still shoot a Glock underwater even without Maritime Spring Cups, though we don’t officially endorse or recommend it. Your goldfish and your toilet bowl will both appreciate your restraint.

Should I upgrade my guide rod & recoil spring?

You can reuse your original guide rod and spring, but for the cost we prefer to use a fresh combination with every build. Springs are wear items with a lifespan that should not be ignored. It’s not uncommon to run a spring out past 10,000 rounds, but we have seen issues during competition use with much lower rounds counts. We prefer to adhere to a “better safe than sorry” mentality, especially when it comes to firearms.

To quote GLOCK directly from an instruction manual: “The recoil spring should be strong enough to move the slide forward reliably to chamber cartridges even if the pistol is somewhat dirty, dry, or the ammunition is not perfect. With an UNLOADED pistol, point it 45 degrees upwards and pull the trigger. While holding the trigger back, pull the side to the rear and release it very slowly. The recoil spring should be able to push the slide completely forward and fully into battery. This test verifies that the recoil spring is strong enough to chamber ammunition despite less than ideal circumstances.”

One important note about the above test: This is intended to be applied to carry and duty pistols using a factory recoil spring weight. It’s common to run a lighter weight recoil spring in a competition/match pistol, especially when using lower powered match ammunition. In these applications, it’s quite possible that the slide will not fully return to battery under spring power alone (especially prior to a thorough break-in), however it will still run perfectly during live fire cycles.

You can see our selection of recoil springs & guide rods along with our various other upper parts by clicking here.

Why does my new slide and/OR barrel seem like it’s sticking?

Our products are engineered and manufactured with tighter tolerances than their factory counterparts. These improved tolerances are what enable us to pull additional performance and accuracy out of our barrels and improved cyclic rate out of our slides.

However, there is no such thing as a free lunch. By tightening up tolerances, you often sacrifice a bit of “forgiveness”. Factory pistols are designed with an intentional amount of forgiveness which allows people to run a wide variety of ammunition in a plethora of environmental conditions right out of the box. The cost of this forgiveness, however, is accuracy and consistency.

Performance can be improved by tightening things up, but it often means that some break-in will be required to get all of the friction surfaces worn in and playing nicely together. Break-in is typically completed after a few magazines worth of live fire.

If you’re experiencing a bit of sticking or “hanging-up” with your brand new slide, barrel, or both, try giving the back of the slide a little “love tap” to make sure it goes into battery. If it rides forward and goes into battery with a tap, then we recommend putting a few magazines through it and see how it feels afterward. That sticking should be gone and your parts should be mated up perfectly, providing 100% function and reliability.

It’s important to note that “hand-racking” alone is often insufficient to properly break in new components. The forces exerted on the pistol during live fire are significantly stronger than anything that can be imparted during hand-racking. They say a picture is worth a thousand words, but we prefer the saying: “A mag of live fire is worth a thousand hand-racks.

What is tolerance stacking and why is it critical when building/upgrading Glocks?

The Glock platform is one of the most versatile and widely-customized platforms to ever exist in the firearms industry. It’s design makes it approachable for the most novice of builders and it’s accuracy and reliability appeal to experienced shooters alike. The options for aftermarket components and upgrades are nearly endless, but this wide array of possibilities is also the cause of one the platforms biggest drawbacks… Enter tolerance stacking.

Every part and component in a firearm is manufactured to a specified dimensional tolerance which is designed to work in concert with the other parts/components that they interface with. In a Glock, for example, the trigger bar must be bent at just the right angle so that it’s high enough to engage with the striker lug, but not so high that it causes a heavy trigger pull. The trigger housing must sit in the proper position in the frame so that the trigger bar sits at just the right height. The slide must interface properly with the frame rails; a little too high and that trigger bar-to-striker lug engagement is affected. There are dozens of relationships like this between parts within the Glock operating system that all have to function perfectly with one another. Once you begin introducing aftermarket parts into the system – especially from multiple different manufacturers – you run the risk that one or more of those parts could be made to a slightly different specification than the factory counterpart.

In many cases, aftermarket manufacturers (NineX19 included) will design their products to have slightly tighter tolerances than the OEM parts. This tighter tolerance provides increased consistency in barrel lock-up, trigger feel, etc. That’s where the improvements in accuracy and performance come from. When you start to tighten tolerances, you also get slightly less “forgiveness” in the system and some friction surfaces need to be broken in and mated to one another over the course of a few magazine’s worth of live-fire. It’s not uncommon for a new barrel or slide to feel a little tight or possibly hang up a bit when it’s first installed and the slide is racked by hand. In most cases, however, a single trip to the range and a box of basic plinking ammo gets everything playing nicely together and provides for 100% reliability moving forward.