Tuesday, May 19, 2015

PM422 Songbird 1.7 3D Printed .22 is Alive! (The Love Gun)

Part 1 - Part 2

Awesome news! After a few revisions, FP of FOSSCAD has printed and tested my Songbird pistol. Some revisions I made since the initial concept include shortening the frame to allow for easier printing, extending the trigger and hammer pins, and enlarging the bore and chamber.

Oh, one other thing. One late night in the FOSSCAD IRC chatroom, the joke was made that rubber band-actuated guns might as well use condoms. Well, FP got wind of the joke and...see for yourself:


PM422 Songbird

That, coupled with the red, white, and blue color scheme, might make this the most American pistol ever created. Here's a video from FP of the test firing:



It works! This is a gun made from printed plastic, some rubber, and a nail and the thing actually works! FP printed two barrels. The first is my design, completely plastic which lasted three rounds before a casing got stuck in the chamber. The second barrel was modified to accept a steel chamber insert. That second barrel lasted 15 rounds and then ruptured just forward of the chamber insert, with no injury to the operator (barrel was ejected to the left). The frame was not damaged. But the important thing to take away from the test is that a printed barrel of just 22mm diameter can take the pressure of a .22LR cartridge as long as the barrel is held in compression. No more giant barrels to compensate for the low adhesion between printed layers! That's a serious step forward in printed firearm technology.

I've made some more revisions for version 2.0 which include a simplified barrel catch, relocation of the hammer bands to the inside of the gun, and more efficient printing.

Concerns? Suggestions? Tell me what you think in the comments.


Wednesday, May 13, 2015

PRT22 Blueprints Are Here!


I just finished the blueprints for the PRT22. Click here to go to the download page. Let me know if you find any issues so I can correct them.

Sunday, May 10, 2015

PM422 Songbird 3D Printed .22 Concept

Part 1 - Part 2
Here's my concept for a printed .22LR single-shot pistol. All of the parts are printed except for the firing pin (a roofing nail) and some rubber bands that will be used instead of springs. Hit the jump for a breakdown of the features.

Wednesday, April 29, 2015

Friday, April 17, 2015

PRT22 Final Assembly and Proof of Life

Part 1 - Part 2 - Part 3 - Part 4 - Part 5 - Part 6 - Part 7 - Finished Pistol

This is it! I went ahead and reblued all of the bare surfaces and scratched areas. Then I assembled it and did some string-assisted test firing at the range. Watch the video below:


I put over 300 rounds through this gun and counted four light strikes. The light strikes could have been caused by cheap ammo or not seating the cartridge all the way, but regardless it ran like a champ. And the best part is that it actually ejects! This is a pistol with no extractor and no ejector and it sends empty casings six feet downrange every time! It works!

Hit the jump for some closeups.

Friday, April 10, 2015

3D Printed Forward Charging Handle

Here's my idea for a forward charging handle that could be used on an AR-based bullpup, such as the one that's being developed over at FOSSCAD
It's a single printed piece that slides along the Picatinny rail on top of the upper receiver. When it is pulled back, one of the feet at the back actuates the catch on the rifle's original charging handle.