The Firearm Blog

The RCI XRAIL (Roth Auto Index Loader) is a auto index loader magazine extension that can expand a tubular shotgun magazine to hold up either 14 rounds (compact version) or 23 rounds (full version).

This video shows the XRAIL mounted on a Benelli M2 Tactical. The benelli magazine appears to be shortened and the gun can now hold a total of 26 rounds.

Now I will be honest with y’all, I don’t actually know what an “auto index loader” is. This is how I imagine the system may work:

* Each of those tubes are a magazine.
* Each of those magazines feeds into the shotgun magazine.
* Once a magazine is depleted it rotates.
* The final magazine contains a spring long enough to feed the shells that are in the shotgun’s magazine.

Because I enjoy making you suffer by awful drawings, here is a graphical representation. The blue box represents the shotgun magazine. The red boxes represents the XRAIL magazines. In this example the shotgun magazine holds three rounds while the XRAIL has three “magazines”, with two holding two shells, and the third a spring.

First two shots


3rd and 4th shot.


Last three shots

I have watched the above video frame by frame and there is seems to be some additional things happening during the magazine rotation. Maybe I am completely wrong … in which case I would have patented my above idea and not blogged about it

The system will be able to work on multiple guns. From what I have seen on youtube Benelli and Remington autoloaders work with the XRAIL. I don’t see why this system could not be adapted to work on pump action shotguns, aside from the fact that if would have to be mounted quite far forward.

A very interesting product. Hopefully it will come to market soon (and probably a video game as well, when game designers get word of it)

Hat Tip: Tactical Life

The XR9 is a prototype 9mm pocket pistol by Boberg Engineering. What makes it special is that the magazine located directly under the chamber. This allows it to have a full size barrel (4.2”). Think of it as a bullpup equivalent in a pistol (not the best analogy but you get the idea)!

What a beautiful looking pistol

Standard black frame, Gen II prototype

The Boberg feed mechanism differs from traditional feed mechanisms in that it draws the cartridge backward from the magazine (see video).

What is not obvious from this view or the video is the rendundancy of the mechanism. The lifting device, consisting of the lifting linkage and the ramp, imparts a kinematically balanced motion to the cartridge as it is lifted. This is important because the cartridge is accelerated rearward an upwards of 2000 g’s. Any impact on the cartridge by the ramp is absorbed by the resiliency of the ramp. This combination, along with containment of the case flange, is sufficient to feed cartridges; however, a top stop is added to prevent any further upward motion of the cartridge.

Even a poorly designed lift mechanism would feed cartridges somewhat reliably when using the top stop alone; however, the Boberg XR9 uses both kinematic balance and the top stop to provide complete and redundant control over the cartridge as it is picked from the magazine, lifted to be in-line with the barrel, and placed into the chamber.

The video:

Specs:

Caliber: 9mm
Length: 5.8”
Height: 4.2”
Width: 0.95”
Weight: 19.5 oz with magazine
Barrel Length: 4.2”
Capacity: 7+1
Action: Rotating-Barrel Locked-Breech
Sights: Dovetail windage, 5.1” radius
Trigger Pull: 6.5 lb DAO
Safeties: 3

It will be very interesting to see what becomes of this pistol.

More info here.

Hat Tip: Ahab

UPDATE: The pistol is expected in 2009.