DEFCAD Newsletter - New in Guncad Pt 1: Printable P80 Jig, Panther-9 SMG, Gatling Crank

September 12, 2022

Welcome to the latest newsletter from DEFCAD! After two deep-dive issues we are returning to covering the latest in guncad, and there are so many new designs that we cannot fit them into a single newsletter! As such, this will be a two-parter. This first part contains some very cool new releases: read on to learn more about them!

Before diving in, we would like to share a coupon code sent to us by the subject of our last newsletter, Laffs Dynamics. Use code LAFFS to get 5% off some very cool laser-engraved magazines at!

Mr. Snow’s Printable G19 Polymer80 Jig

As many reading this may know, ATF’s “receiver rule” 2021R-05 took effect on August 24th, 2022. Among other things, this rule absurdly declared that selling unfinished frames / receivers and the tooling / jigs required to finish these items was equivalent to selling a firearm; in reaction many companies, including Polymer80, stopped selling completion jigs.

This rule has since been partially enjoined, but in any case the guncad world has already done what it does best and created a workaround. Mr. Snow developed, tested and released this printable P80 jig for G19s in less than a week following the rule’s effective date. It is available for download now.

This unassuming jig represents the best of guncad. It is, of course, a functional piece of engineering - never again will the law prevent someone from acquiring a jig to finish their P80, and indeed even absent a legal threat, printing this jig is far less expensive than buying one. But the story of this jig is emblematic of guncad’s symbolism: we will always engineer our way around your laws. It is, ultimately, this symbolism that they fear the most. Major congratulations to Mr. Snow for creating this fantastic work!

Mr. Snow’s Printable AR-00 Lower

Mr. Snow has been productive lately! A second new release from him is a new AR-15 lower that is modeled on Ghost Gunner’s AR-00 lower and uses the metal buffer tower from the AR-00 kit. Using the metal buffer tower with a printed lower allows for a much thinner overall lower, closer to the ergonomics and aesthetics of a traditional metal lower receiver.

The perennial problem with printable AR lowers is: how do you secure the buffer tower? This is one of the thinnest parts of the lower, but it also takes some of the most force. Over the years several different solutions to this problem have been found: the UBAR lower reinforces the tower with a U bolt, Hoffman’s lower reinforces it with a hose clamp, and PY2A’s lower uses custom cut and bent metal reinforcement.

Upon Ghost Gunner’s release of their metal AR-00 kit in January 2022, it was immediately noted that the metal buffer tower piece could be repurposed for use in a printed lower. Mr. Snow is the first, to our knowledge, to actually do so. If you are looking for an AR lower with a thinner profile or more traditional AR ergonomics, this lower is a good option!

Mussy’s RONI v3

In a previous newsletter we covered printable pistol chassis / RONI designs, and Dr. Mussy’s designs took up over half of the items. He brings us yet another new design with his RONI v3, which fits G17s, G19s and G44s. As is usual for Mussy designs, this release contains several alternate designs for various parts.

As described in the previous newsletter, a handgun chassis or RONI allows you to “upgrade” your handgun and add features that a handgun wouldn’t normally have, like a brace, foregrip or extra accessory rail. Sometimes this requires disassembly of your firearm or installation of the internals and slide into the printed chassis; In the case of Mussy’s RONI design, however, no disassembly is necessary, and the pistol can simply be slid right into the chassis.

The DLC included with this release contains several different brace options, including a sliding tailhook, as well as several endcaps to interface with other popular printed stocks and braces. Also of note are different foregrip / retainer designs. Customize and print yours today!

Two New Professor Parabellum Releases - SMG and Mine

We are pleased to announce the release of two new Professor Parabellum designs! The Panther-9 Mk2 is a fully DIY hybrid machine pistol that uses 1.5” square tubing for the upper in combination with a printed lower; his Gorazde A/P mine release is a reference model for a plastic-bodied antipersonnel mine, of a design used in the Yugoslav civil wars.

The Panther-9 Mk2 is an update of a pre-3DP Professor Parabellum release. The original Panther-9 SMG was made entirely from metal parts. This new version uses a similar upper and bolt design, but the lower is now 3D-printed and accepts Glock magazines (aftermarket or printable.). Also of note is the DIY ECM barrel. The original Professor Parabellum designs, as detailed in an earlier newsletter, are a goldmine of cool design ideas: it is always wonderful to see the man himself revisit these designs and update them in light of new technologies!

The Gorazde A/P mine reference model is a fascinating example of simple but effective technology. The majority of this item is plastic - only the striker, safety pin, spring and ball bearing (and, of course, the charge) are not made from polymer. Professor Parabellum’s release package does not contain explicit instructions for making this item, but it does contain detailed measurements for each part. This Gorazde mine was used in the Yugoslavian civil wars of the mid-90s, and is named for the town near where they were first discovered. They are thought to be copied or inspired from the Commonwealth-developed C3 “Elsie” A/P mine.

Gatling Crank by PlasticToFreedom

The Gatling Crank or “GatCrank” by PlasticToFreedom is a trigger device to assist with rapidly pulling a semiautomatic firearm’s trigger. It mounts onto the trigger guard of the firearm - each full turn of the crank actuates the trigger four times. It is noted as working on AR-15-style rifles, Ruger 10/22 rifles and some AKs.

The 3D-printable GatCrank is of course inspired by the commercial product of the same name, although this product only actuates the trigger three times per crank instead of four! Some custom fitment may be required for your print, particularly the length of the “pushbar.” Two variants are included in the release package.

This is only half of what's new in guncad - we'll be sending out a second issue soon containing the latter half! It is the goal of the DEFCAD newsletter to highlight major new guncad releases, and we will continue to do so - review our back issues and find all of these projects, and many more, at DEFCAD!


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