3D Printed Imura Revolver Hybrid Development

Gun Watch ^ | 15 September, 2014 | Dean Weingarten

[marktwain]

An innovative 3D printed hybrid revolver design is being worked on as tribute to 3D printings first martyr,  Yoshito Imura.  Imura was arrested for 3D printing some plastic, blank firing guns in Japan.  The development would fire from the bottom of the cylinder, as did the original blank firing plastic gun.   The new design has hybrid features, including steel chamber sleeves and barrel liner.

 As seen in this computer image of the developing design, the revolver is meant to be double action; that is, one pull of the trigger will rotate the cylinder, cock the striker, and release it, firing the charge, whether cap and ball, blank cartridge, or conventional cartridge.

 

It is an ambitious design.   Here is a link to tweets on its development by WarFairy, Frostbyte, et al.  Double action revolvers are more complex than single action revolvers such as the original Imura design.  I see one weakness that the designers have probably noticed.   There is very little tensile strength in the proposed design.   Convention revolvers use a metal frame to contain the forces generated by firing a charge.   The chambers contain the pressure at right angles to the barrel, but the frame, chamber, and case, if one is used, must contain the pressure to the rear.   The projectile contains the pressure to the front, where the force is used to propel it out the end of the barrel.

 

If I were designing this revolver, I would consider the use of a bolt as a center pin for the cylinder to turn on.   A simple backplate of steel could be made to screw the bolt into, adding tensile strength.  It would not need to be circular, as long as it supported the rear of the chamber being fired.  Removal of the bolt would allow the cylinder to be removed from the side of the design, so as to facilitate loading.  Many conventional revolvers use this design feature.

While development is still in progress, at least one prototype cylinder has been produced.   Looking at the surface of the cylinder, it appears that a hobby type printer was used.   More images are available at this site.

Hybrid designs such as this offer unique advantages for the production of inexpensive firearms outside of normal channels of commerce.

©2014 by Dean Weingarten: Permission to share is granted when this notice is included.  Link to Gun Watch

[marktwain]

A big washer for the backplate would work. Use a nut to tension it

[W.]

When I saw the pic, the grooves in the cylinder looked familiar:

The Webley-Fosbery automatic revolver.

[Dead Corpse]

Cool.

[Talisker]

The Webley-Fosbery automatic revolver.

The revolver used to shoot Miles is almost correctly identified by Sam as a Webley-Fosbery; he erroneously identifies the gun and mispronounces the name (as "Foresby"), saying, "It's a Webley-Foresby .45 automatic, eight-shot. They don't make 'em anymore." While the .38-cbl. did have an eight-round capacity, the .455-cal. (not .45-cal.) did not. Also, though some .455 Webleys were modified to fire the more common .45 ACP cartridge by use of half-moon clips, unless specially modified on an individual basis, there was never a .45-cal. eight-shot Webley-Fosbery Automatic Revolver. In the original 'Dashiell Hammett' (q) novel the gun is correctly identified as a "Thirty-eight, eight shot". All Sam says about it is, "They don't make 'em anymore."

From: Maltese Falcon trivia, IMDB, http://www.imdb.com/title/tt0033870/trivia

[W.]

Quite the contraption, eh? When fired, the top half of the piece would slide rearward on the frame, there was a pin protruding upwards that the grooves in the cylinder would track in, which rotated the cylinder and cocked the hammer, IIRC. Brain tells me somebody produced a revolver that when fired, would spit the empty case out of the rear of the cylinder. Ow, my eye! Har!

[marktwain]

Yes, there were several automatic ejecting designs, as I recall.

It makes some sense if you can reload one cartridge at a time.

[VRW Conspirator]

Bou-ya, gran-ma