What are the brass bars on this gun prototype?

Factual Questions
1

I’m hoping somebody can explain the odd-looking parts of this gun.

Specifically:
[ol]
[li]what are the brass bar sections you see just behind the trigger grip and the forward grip?[/li][li] Why did they put notches (kind of like the rack in a rack and pinion system) on the barrel housing ahead of the forward grip?[/li][li] Am I correct in assuming those are buttons on and above the forward grip (for use with target tracking systems)?[/li][li] Why does it have “not man fireable” labels on it? What would happen if a person tried to fire it right now?[/li][/ol]

Here’s a link to the article about the gun:

I know almost nothing about military guns, and even less about civilian ones.

2

  1. They notches are pretty clearly to engage an adjustment gear to move the unit back and forward, I assume the think that looked like a faucet would be turned to adjust it. Why this is, I don’t know.

  2. Just guessing, but it could be that the physical trigger is disengaged and the gun is fired through some other internal mechanical link.

3
  1. I believe it’s part of the rear mount to the test stand.
  2. They’re used for attaching accessoriessuch as flashlights or bipods.
  3. That’s the forward test stand mount and adjustment wheel, not part of the gun. Although a forward grip will probably be a mountable accessory when it’s in service.
  4. It’s set up to fire remotely while on the stand, so the trigger is disabled.
4

1 - The “brass bars” appear to allow forward and back adjustment of the trigger assembly/housing. Possibly for balance or to better fit the shooter?

2 - The “notches” appear to be a Picatinny rail for mounting assesories such as lights, lasers, or grips.

http://www.brownells.com/items/picatinny-rail.aspx

4 - The “not man fireable” label is written in Canadian but my guess is that this is an electrically-fired weapon and does not require the usual manual trigger assembly to operate.

5

That particular sample is mounted in a test stand. So it’s been modified to be remotely fired, so possibly the manual trigger has been disabled. The “not man fireable” labels aren’t permanently stamped into the weapon, they’re just stuck on for that specific one. So it can be difficult to tell what’s part of the stand, what’s a standard part of the rifle, and what’s an add-on to the rifle.

6

Those aren’t brass bars: they’re the same aluminum as the test stand behind the gun. But due to their angle, the lighting gives them a yellow cast. The metal doesn’t actually touch either of the pistol grips; it’s a couple inches back. If you were looking exactly side-on to the gun, you couldn’t see those pieces at all (just the end caps, which are the black plastic squares with bolts in the center).