cc-settings-icon BUILD AT HOME
80% Arms sells AR-15 and .308 80% Lower Receivers, 80% Lower Jigs and other accessories which allow you to legally build a firearm at home in most states.
cc-gun-icon INCREDIBLY PRECISE
We utilize state of the art 5-axis CNC machines to mill all our .308 and AR-15 80 percent lower receivers to incredibly precise tolerances using premium billet aluminum.
cc-hand-icon RIDICULOUSLY EASY
We also offer our patented AR-15 and .308 Easy JigsĀ® which is the first 80% lower jig that makes it ridiculously easy for a non-machinist to finish their 80% lower in under 1 hour with no drill press required.
cc-thumbs-icon 100% SATISFACTION GUARANTEED
Products manufactured by 80% Arms carry a lifetime warranty against manufacturing defects. We will promptly replace or repair any product that we determine to be defective.

Pistol Barrels

We love tinkering with our guns and we assume you do too! Any aftermarket barrel’s accuracy is going to be tough to compare to an OEM Glock barrel. However, that’s not to say that there aren’t some pretty fantastic aftermarket Glock barrels out there. One of the easiest modifications you can make to any handgun is by changing out the barrel. For some it may be as simple as an aesthetic motivation to have a different color barrel like silver or gold. But some provide functional advantages as well. 

G19 Fluted Barrel

The advantage of having a fluted barrel is that you get to enjoy some weight savings. With the removed material for the ‘fluted’ design, some weight is reduced from the barrel while still maintaining the required strength and stiffness in the barrel. G19 barrels that come with our Wraith slide, Shadow slide and build kits are black and straight-fluted, match-grade barrels. We’ve tested tens of thousands of rounds through them and not only do they perform up to snuff, they also fit great with any Gen 1-3 G19 slide. If you want a silver barrel to have that classic contrast with a black slide we also carry the True Precision 9mm Stainless Steel G19 Barrel which supports Gen 1-5 pistols. True Precision’s G19 barrel design is an improved design for better overall fitment compared to the OEM barrel as well. 

Glock Ported Barrel

If you opt for our Wraith slide and choose to pair it with a Glock ported barrel for your GST-9, you’ll enjoy the windows in the slide that double as vents. When using a Glock ported barrel, gas will escape from the small openings towards the front of the barrel which will line up perfectly with two of the Wraith slide’s windows. As the gas pushes out after firing a round, it helps to mitigate some of the recoil which sort of acts like an internal compensator — creating a flatter shooting experience. The ported barrel and slide combination is certainly a performance advantage we hope our customers take advantage of. 

Glock Threaded Barrel

Another fun option for builders to take is to opt for a Glock threaded barrel. Having a threaded barrel allows for a wide variety of accessory components to be installed and used such as compensators or suppressors. Be careful of some state laws though. In California, handguns with threaded barrels are considered as “assault weapons.” And when you’re not using any barrel devices, the threads can be covered up with a stylish thread protector. Some people use pretty shiny ones not unlike how knife fans will have artisan beads and paracord connected to the back of their knives. 

Barrel Length Compatibility 

It completely makes sense to want to deck the GST-9 out, as we’re all about modularity and customization.  We get these questions about this often so let us help make it easy and clear for those who want to build a GST-9 in a longer format than a G19:

Glock 19x Style- Lucky you, no barrel change needed here. Just slap on the large grip module with your existing slide, G19 barrel and you’re golden. 

Glock 17 Style- Due to the frame and internal parts being modeled after an OEM G19, in order for a GST-9 to look and feel like a G17 you’ll have to look for a few things. The slide you purchase will have to be a G19L slide. The Glock barrel you buy will also need to be a G19L barrel. They’re typically sold as a set with the slide so you don’t buy the wrong barrel size on accident. Make sure that the product you buy is either Gen 1 - 3 or 5 as well so that the barrel’s locking lug will fit correctly onto the GST-9’s front rail.

Glock 34 Style- To achieve a Glock 34 length you’ll need a G19XL slide and barrel. Also make sure that the slide and barrel is for Gen 1-3 or 5 so that it will be compatible with the GST-9’s internals. The Gen 4 is not compatible. Pro tip: if you attach an external compensator to either our Shadow or Wraith Slide, you can also achieve the G34 length in that way.