Issue #30: DIY Glock Trigger Housing, DIY Mac Uppers, High Temp PLA Pro, Smokeless Powder
Oops, all betas!
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It appears that the last two weeks in guncad were sparse in new releases but very active in betas and “coming soon” announcements! Read on to find out what’s coming in the next few months:
New Releases:
In this section, we cover new releases that we find notable. If something catches your interest, go download and start printing!
Printed Glock Trigger Housing from PrintYour2A
The mission to DIY every part of the Glock progresses! Based developer PrintYour2A recently released a printed version of the Glock trigger housing. This is not just a STL version of a reference model - several geometric changes were made to facilitate printing, as can be seen in the photo.
PrintYour2A notes that this particular model is designed to fit in Gen 4 and Gen 5 frames, but uses Gen 3 trigger parts. One imagines that it could easily be adapted to fit Gen 3 frames as well.
There’s no shortage of printable triggers, the other major plastic part in the Glock FCG, so the next step will be to create bending jigs for some or all of the trigger bar components. Actually, that already partially exists! The technology is within reach!
Calibrate Your Printer Perfectly with PerfectFit
The words “Calibrate Your Printer” should be burned into the eyelids of every new gun printer. Taking the time to ensure your prints are clean and accurate will resolve so many of the issues you’ll encounter.
Fortunately we live in a Bambu world, where these printers are calibrated fresh out of the box. Good riddance to spending weeks tweaking your Ender before you could get a halfway decent print!
Still, you can make your Bambu (or Qidi, Elegoo, Prusa, etc.) even better with some basic calibration steps - and the recently-released PerfectFit project from tayloraaron078-tech may be the next best thing for performing those steps.
The PerfectFit software provides a wizard that guides you through each step of calibrating a printer for a particular filament - starting with nozzle temp and flow, hitting speed and retraction, and verifying accuracy.
The actual tests being performed are the same tests we’ve performed for years now - what PerfectFit does is present them in an incredibly convenient and clean step-by-step format. It also automatically generates a profile for your chosen slicer (either Orca or Bambu) for you to import and start using.
Printers wishing to supercharge their printers should definitely check this project out! I expect to refer to it in some upcoming education :)
Updates:
In this section we will mention updates to major releases - fixes, new variants, etc.
M1337 Meshes Getting STEP Conversions
The M1337 is legendary, that goes without saying. Even more legendary is the fact that it was designed in Blender of all things. An impressive feat, but that also means that the source files are meshes - there are no STEPs. Until now!
Several community members have taken it upon themselves to convert the M1337 into STEPs. This is not as simple as running it through a converter - often it involves partially or even fully entirely re-modeling the part. It’s a lot of work, and the devs involved are doing it for free.
Nopel has created a page on his website to collect these converted parts, so that everyone can benefit. A large number have already been modeled, and the page includes a form for you to submit your own re-modeled parts to add to the list.
Fantastic work guys!
New Betas:
In this section we round up recently opened betas. Help support development by joining these betas and testing!
Twitch V3.0 - Reset Trigger for MPA Defender
So we’ve got Mac reset triggers, but for the most part, these are only for PCC-style Macs using AR FCGs. But the people (i.e. me) want to reset trigger a pistol Mac (i.e. a Mac that Looks Like Mac™)!
Developer Toadlicker556 comes to the rescue with his Twitch v3.0, a reset trigger design for the MPA Defender. In his notes he claims that this enables a cyclic rate of 1,300 RPM - perfect for fighting in a phone booth! 2-position and 3-position versions are both available.
This is the third iteration of this beta, so it’s certainly coming along - but it’s still a beta. If you’ve got a Defender, download and help test!
DIY Your Own Smokeless Powder, With Only a Small Chance of Death
Sometimes I argue with myself about whether I should include stuff like this in the Digest. What we have here is a guide to DIYing smokeless powder, which in practice means DIYing nitroglycerine from battery acid, drain cleaner and other fun chemicals. Nitroglycerine, once synthesized, is highly unstable and can detonate simply by looking at it funny. The process of synthesis also produces caustic fumes which can kill you, or make you wish you were dead. DIY chemistry is not a joke.
And yet - there was a time where we all thought that printing your own gun was a guaranteed way to lose your fingers, or your life. There was a time where we thought that ECM byproducts would poison you. We found ways to make them acceptably safe. I believe we can do the same with stuff like this as well.
So I’ll share this information - not because I think it’s ready for prime time, but because I believe that there is at least one person out there who possesses the knowledge and skill to take the process described here, and further refine it. And that iteration, over time, will produce a process that we may someday take for granted, just as we take the concept of squirting a gun from plastic for granted today.
Are you the person who will take on this project? This is your call to action!
New Pistol Betas from UberClay
Another day, another build for bizarre and obscure pistol parts kits. Developer Uberclay has taken up the mantle for popping these out, and he’s got two new ones for us! They are:
The R345, a Recession Ruger frame that accepts the Ruger P97 and P345 models, both in .45ACP
The Stoeger STR-9, a standard (non-PCC) frame for the Stoeger STR-9 9mm
They’re both in open beta, so grab a parts kit from EGP and come help test!
Look at the sexy Peacemaker grip on that R345!
Active Reset P320???
We’re just full of great ideas today, aren’t we?
Duality Arms Co, manufacturer of the “Rapid Assist Tactical Load-Reset Trigger” for the Kriss Vector, has been working on a side project which he calls the Mamba. It’s a drop-in reset device for the (in)famous P320, allowing you to shoot your own leg at rates never before seen!
Okay, jokes aside. I think most people are coming around to the idea that the P320’s “danger” is quite overblown, and that its awful reputation is due far more to Sig’s disastrous PR strategy than its actual technical merit. A highly litigious gun company that relies on lawsuits to gain market share - where have we heard this before?
As such, a resettable P320 could actually be quite cool. What’s cooler is the fact that Duality Arms is releasing this device as a “community project” - while their company developed it in-house, they were not able to bring it to the point where they feel it’s releasable as a product. As such, they gift it to the community to iterate and play with. I think that’s fantastic! They’ve even provided a video to demonstrate installation.
If you’ve got a P320 sitting around, why not try this out? And if you don’t have one - I hear they’re pretty cheap nowadays!
Open Beta for Kel-Tec CP33
Developer WmHerrin recently reminded us that he developed a DIY FCU for the Kel-Tec CP33, and it’s in open beta, ready for your testing!
It appears that the Kel-Tec adopts a FCU chassis design that serves as the serialized firearm, similar to the P320. It’s a neat experiment, although it’s unclear how common parts kits for the CP33 are. Regardless, any DIY gun is a good DIY gun!
Reset Your UMP 11/9
We’ve got lots of UMP-related stuff in today’s issue! Starting off with this project from MSRPatton80, a modification to the UMP 11/9 to allow the use of either the RAD or the U-DIS reset devices in this build.
This is noted to be in an alpha state, and documentation notes that while it has been tested for functionality, it has not been tested for longevity. If you’ve built an UMP 11/9, print this out, give it a try and report back!
Coming Soon:
This section lists announcements or previews for projects that have not yet hit open beta. Keep an eye out for further news about these projects!
UMP-VO Gets Detent Delay!
The UMP-VO, one of three popular UMP builds (the others being the UMP 11/9 and the UMforthePoors), is getting a remix to add detent delay functionality!
Like other detent delay mods, like the Holdup or Maelstrom, the Detent-Delayed UMP-VO appears to be using ball bearings mounted in the upper to delay the bolt. I love to see a good idea spread around!
This mod does increase the charge weight, leading developer FoapsFiles to recommend an OEM EVO charging handle for extra strength.
The video included in the Reddit post is apparently the first production test of the design - hell of a first test lol. Hopefully we’re not too far out from release!
PWC DIY Dropping Soon, in PCC and Pistol Configurations
Time for a check-in on the PWC DIY project! Last mentioned in Issue 18, this project is dedicated to creating a DIY Mac upper that, unlike other options, requires no custom trunnion. So what’s new?
Quite a lot! The standard PWC DIY, configured as a PCC, has adopted detent delay - we keep seeing that in this issue! - and appears to be quickly progressing towards open beta. Even more exciting for me, a pistol version has been developed, allowing you to create - say it with me - a Mac that Looks Like a Mac™!
I spoke with developer nightalliance about the PWMP DIY, and he told me that it will have both the same detent delay as the PWC DIY, and will have a super safe functionality! I’m in love.
Both projects are in closed beta at the moment. Can’t wait to see more updates!
Fair Deal V2 Printed S&W15-22 Mag Coming Soon
The Fair Deal, released in 2024 by GeneralCuster75, is a printable magazine for the S&W15-22. Two years later, the same developer is releasing an V2 of this design!
From his commentary, the V2 will address several issues that could manifest in the original V1, including “rimlock, double feeding, nose diving cartridges, binding followers, and aesthetics.”
It sounds like actual CAD work is complete and the remaining work involves documentation and media. Expected release date is August 3rd - just a few days away from when this newsletter drops!
News:
In this section we’ll review major news events either originating in the 3D2A space, or particularly pertinent to this space.
FossMG9 Voted as Next Design for World of Guns
Well that was fast! Back in Issue 27 we reported that the FossMG9 was put on the ballot for the popular gun-building game World of Guns.
We solicited for votes, and you answered! It very quickly rocketed to the top of the ballot, and has now been officially selected for inclusion in the game. Incredible!
The next steps are for the WOG team to model and animate the design, so it isn’t going to drop in immediately, but it won’t be long now. Stay tuned!
Polymaker Releases HT-PLA Pro
If you’re even tangentially present in online 3D2A spaces you’ve likely heard this news already - Polymaker, the preferred 3D2A-friendly filament manufacturer, has launched a new PLA formula called “HT-PLA Pro.” Why’s everyone so excited? Because this new filament advertises significant improvements over normal PLA Pro!
The two numbers everyone is noting is 2x impact strength and heat resistance up to 150C. What do these claims actually mean, and can they be trusted?
Examining the TDS’ for PLA Pro and HT-PLA Pro reveal interesting numbers. Regarding strength - across many tests, these two filaments appear to be in the neighborhood, but the Charpy test for impact resistance shows that HT-PLA Pro is significantly worse than PLA Pro.
How does this square with the marketing claim? Polymaker’s launch video goes into detail about their tests, and claims that the “better impact strength” claim comes from a combination of real-world impact factors which the individual Charpy test doesn’t represent. The TDS and related marketing also notes that the mechanical properties improve dramatically after annealing at 100C for 30 minutes.
As for temperature resistance, the 150C claim may come from the “Vicat softening temp” number, which tests when a plastic begins to soften to a sufficient degree that may cause warping, bending or sagging. Standard PLA Pro has a Vicat softening temp of less than half of HT-PLA Pro.
Discussion abounds on what to make of this new filament. If it works as claimed, then we’re getting a material near the cost of PLA Pro, as easy to print, with similar (or better?) mechanical properties and far more heat resistance. That’s exciting!
But only time will tell if the claims hold true. We’ll keep an eye on real-world test results as they roll in.
Commercial Corner:
This ever-changing section focuses on a particular subject of interest. Today’s focus are some new product options from our friends in the community! Go check them out!
Maelstrom Pro Delayed Blowback Mac-11 Uppers Released!
Long awaited and teased, our friends at Riptide Rails have launched their Maelstrom Pro series of Mac-11 uppers! They’re sleek, they’re sexy, but most importantly they introduce a detent-delayed blowback function!
This delay function is provided solely by the upper itself - the Mac bolt (not included) requires no modification to function in delayed mode. Very cool!
Beyond this cool functionality, the Maelstrom Pro series offers several other upgrades compared to a traditional Mac upper. Maelstroms are monolithic, milled from a single block of metal instead of produced via bent sheet steel. They offer a continuous pic rail and a folding, non-reciprocating charging handle.
Two options are available: a 5.5” version and an 8” version. Both appear to be out of stock at time of writing - I think they sold fast when they were dropped. Join the waitlist to grab them when they come back in stock!
Mid State Firearms Relaunches Breek Castle Muzzle Device
The Breek Castle Blast Shield by Breek Arms was and is the recommended method for mounting a FTN suppressor to a barrel - this is the case in the FTN3, FTN4 and FTN5.
This is a two part system: a muzzle device threads onto your barrel’s threading and provides a 13/16 threaded mount point, and the “Castle Blast Shield” screws onto the 13/16 threads. The FTN uses this by embedding the Blast Shield into the suppressor, creating a very secure metal-on-metal mounting system.
Bad news: Breek Arms discontinued these parts in 2025. Good news: Mid State Firearms has relaunched the product, making this excellent mounting system available again!
Remember that you’ll need to get both a mounting device compatible with your barrel and the Blast Shield itself. Grab one and go build a suppressor!
Quartermaster Arms Offers Engraved FTN Washers
Speaking of FTN suppressors - the $0 tax stamp has created a significant demand for products related to serialization, and many businesses are pivoting to fulfill this demand.
One such business is community member and FFL/SOT Quartermaster Arms, who reached out to the Digest to let us know he is selling laser-engraved washers for FTN suppressors! Price is $20 per washer.
He’s located in Virginia and ships nationwide. If you’re looking to serialize your FTN in this manner, consider hitting him up!
Other Links:
This section will collect any other links I find interesting. These may be older designs I want to share, releases I find notable but don’t have much commentary on, or anything else that catches my eye.
Sometimes I find a design that I somehow missed when it first came out, but which is easily cool enough to be worth mentioning. Back in Jan 2025, developer shadowhunter556 released a build that wraps a BRN-180 bolt and barrel inside a P90 chassis, and feeds it with a DIY P90-style magazine. It’s called the P90BLK. Give it some love!
Apparently there’s a shooting sport in Germany based around firing a certain number of shots within a 60 second period. Time management is key here. To help with this, developer Tritschi created a DIY visual 60 second timer. Very cool!
I often describe the PEN15 as a “firecracker launcher”, but now you can shoot a literal M80 out of your PEN15 with this Ramset M80 barrel. Stay safe guys!
This AR-15 spring maker was uploaded recently, and I thought it was neat. Upon review it looks like a clone of another design from back in 2023. I still think it’s neat though!
About the Guncad Digest:
Thank you for reading this issue of the Guncad Digest! Please send us your feedback and suggestions for improvements on the issue.
The Guncad Digest is sourced using the very excellent Guncad Index, from /r/3D2A, and from readers like you. If you know of a project you think should be featured, send it our way!
This issue was compiled and authored by Alyosha from 3D2A.com. We sell high quality parts kits for some of the best DIY guns available - if you’re looking for your next gun build, come check us out!
The DIY smokeless powder piece is particularly intriguing, as nitroglycerine produced from this method would perhaps be far more useful for manufacturing DIY dynamite than smokeless powder. For the possibilities that entails I leave it to the reader's imagination.