{"id":123890,"date":"2020-03-22T13:26:15","date_gmt":"2020-03-22T17:26:15","guid":{"rendered":"https:\/\/www.gunsamerica.com\/digest\/?p=123890"},"modified":"2020-03-22T13:26:15","modified_gmt":"2023-09-06T14:01:39","slug":"modular-glock-gst-9-80-percent-arms","status":"publish","type":"post","link":"https:\/\/gunsamerica.com\/digest\/modular-glock-gst-9-80-percent-arms\/","title":{"rendered":"The World’s First Truly Modular 80% Glock: The GST-9 By 80 Percent Arms"},"content":{"rendered":"\n
\"The
The frame that I received is a pre-production model, so it does not have a stippled grip: all production models will be stippled. I outfitted my GST-9 with a bunch of aftermarket parts in order to build the gun of my dreams. Most noticeably, I chose to use Rival Arms’ slide, barrel and Tritium MOS height sights, add a HOLOSUN HS507C-V2 reflex sight, and attach Rebel Silencers SOS-450 suppressor.<\/figcaption><\/figure>\n\n\n\n

What’s better than a Glock 19 or a Glock 17? How about a handgun that can be configured to both, and everything in-between! The GST-9<\/a> is a 1-3 generation compatible, modular 80% Glock Frame<\/a> that is currently available for pre-order from 80 Percent Arms. By removing two pins in the grip, you can swap the grip extension for a short or tall grip extension that matches the length of a Glock 19 and Glock 17 grip respectively. This simple, yet ingenious design provides you with the options of a Glock 19, 19X, 19L and 17 (with the 17 requiring a Glock 17 slide and barrel). And, of course, because it is not a firearm from the factory, it can be shipped to your door and requires no registration in most states. <\/p>\n\n\n\n

What Makes the GST-9 Different?<\/strong><\/h4>\n\n\n\n

As mentioned, the GST-9 is a modular frame that accepts two different grip extensions. One is shorter, resulting in a grip the same length as a Glock 19. The other is longer, configuring the grip to the same length as a Glock 17. Naturally, magazine compatibility changes when you swap these grips out. When in Glock 19 configuration, you can run Glock 19 magazines and larger. Ditto for the Glock 17 configuration of course.<\/p>\n\n\n\n

\"The
With the large grip extension, this handgun features a G17 length grip, and G19 length slide; configuring it to be a G19X.<\/figcaption><\/figure>\n\n\n\n
\"The
Here, the large grip extension has been switched with the short one; making this handgun the size of a G19.<\/figcaption><\/figure>\n\n\n\n

This modular aspect is not the only distinguishing characteristic of the GST-9, as a lot of engineering has gone into this project. This build also features a unique mating interface between the frame and the slide due to the frame rails being extended three times longer than their normal length. This one detail alone creates a more controllable recoil impulse, better repeatability, and greater accuracy. 80 Percent Arms even went so far as to nickel plate these rails which results in reduced friction and increased longevity of the firearm. You won’t have to worry about rust, dirt or grime locking your slide up, even when liquid lubricants on the rails have long since been cooked off.<\/p>\n\n\n\n

The GST-9 frame accepts any Gen 1-3 Glock 19 components, accessories, and holsters. This makes the GST-9 the first and only 80% lower that fits in standard Glock holsters. Because you can use any 1-3 Gen parts, you can build up the frame with the exact mix and match of components that you want. Other notable features of the GST-9 frame include the full Picatinny rail for an array of attachments, an undercut trigger guard and a high beavertail, scalloped mag release, no finger grooves, and gas pedals. All of these features equate to a firearm that is more ergonomic, flatter shooting, and consequently more fun to shoot.<\/p>\n\n\n\n

\"The
Notice the longer frame rails, gas pedal, and textured trigger guard.<\/figcaption><\/figure>\n\n\n\n

If these features don’t quite pique your interest, 80 Percent Arms are sure to capture it eventually as they release more grip modules for the GST-9. There will be more grip modules coming in the future, like competition magwell, different contours for different ergonomics, etc. <\/p>\n\n\n\n

When\/Where Can I Buy One?<\/strong><\/h4>\n\n\n\n

You can currently get 30% off MSRP by preordering a GST-9<\/a> frame, or full build kit on 80 Percent Arms’ website. As suggested, you will be able to purchase either the frame and jig (sold as separate items for legal reasons) or the full kit which includes everything that you need for a functioning gun. Prices range from $79.99 – $699.99 currently but will go up as soon as they start shipping in the spring of 2020 the pre-order sale ends.<\/p>\n\n\n\n

There are only a couple of unique aspects to my build when compared to 80 Percent Arms’ complete build kit. For starters, I have a threaded barrel, tritium MOS height sights and a slick nitride coating on the barrel. For about $400 less, you can preorder the GST-9 complete build kit and get a high-quality “Gucci” gun that only differs in these areas.<\/p>\n\n\n\n

\"The
For my build, I chose to use A Rival Arms Slide and Tritium MOS height iron sights accompanied by a HOLOSUN HS507C-V2<\/figcaption><\/figure>\n\n\n\n

Doing the Other 20% (AKA Building)<\/strong><\/h4>\n\n\n\n

Now for the fun part: finishing the 80% lower to turn it into a firearm. This is the first 80% lower that I have started and completed on my own. In the end, I proved that if I can do it, anyone can. We have full guides published on GunsAmerica on how to complete 80% Glock builds in detail, so I’ll skim over the process here:<\/p>\n\n\n\n

\"The
These are the parts that will make up my completed firearm.<\/figcaption><\/figure>\n\n\n\n

Starting at the beginning: before I began the modifications to the lower, I noticed a few things. The jig that you get from 80 Percent Arms is extremely robust, being constructed of glass-filled polymer, it is 3x stronger than other jigs on the market. It also has deeper drilling guides, helping you drill perpendicular to the workpiece. And once I had all five bolts tightened down in the jig, it was locked down extremely tight, resulting in exact and precise modifications.<\/p>\n\n\n\n

\"The
The GST-9 Frame goes into the jig. Then you bolt it shut and begin to work.<\/figcaption><\/figure>\n\n\n\n

One other note: The jig comes with all of the required tooling for completing the lower.<\/p>\n\n\n\n

The First thing that I set out to do was to drill the appropriate holes through the frame. You cannot mistakenly drill the incorrect hole, because the drill guides are the exact size of the bit that you need to use. I chose to use a cordless drill for this task and I knew that I could potentially skew a hole. I mitigated this by drilling halfway through one side, flipping the jig over, and finishing the hole from the other side. In the end, this method worked out great.<\/p>\n\n\n\n

\"The
The beefed-up drill guides really helped keep everything square.<\/figcaption><\/figure>\n\n\n\n

Next up, I removed the excess material from the top of the frame with a Dremel and the provided bit. I cut this material down until it was almost flush with the frame and then switched to a flat file wrapped in 220 grit sandpaper. I did this in order to grind these tabs down square to the frame without removing excess material. The last step was to remove the material in the barrel channel, which I also did with a Dremel and sandpaper.<\/p>\n\n\n\n

\"The
Dremeling down the tabs takes very little effort. Be careful to not over-cut and eat into the jig.<\/figcaption><\/figure>\n\n\n\n

Once this was done, I removed the bolts from the jig, dropped the lower out, and I was ready to start installing parts. This whole process took me approximately 10 minutes which I would say is a long time because I was taking extra care to make everything perfect and pretty. <\/p>\n\n\n\n

\"The
Filing the tabs down the last little bit, keeping everything square.<\/figcaption><\/figure>\n\n\n\n

Once the lower had been modified, I watched a couple of videos online on how to assemble the remaining parts and then dove into that aspect. I installed OEM Glock 19 internals and a Rival Arms<\/a> RMR cut G19 slide, threaded barrel, and night-sights with an accompanying HOLOSUN<\/a> HS507C-V2 reflex sight. Completing the lower proved extremely easy, as the steel rails for the GST-9 dropped right into place and all of the pins lined up just perfectly. Once the lower was completed, the slide racked right into place. With that, my build went from a hunk of plastic to a completed firearm in under an hour.<\/p>\n\n\n\n

\"The
Once the tabs are ground down, holes are drilled and the front barrel channel is cleared, this is what you end up with before installing the frame rails and internals.<\/figcaption><\/figure>\n\n\n\n

Components Used in My Build:<\/strong><\/h4>\n\n\n\n