[Disambiguator]

That photo is odd.

[going hot]

appears to be a belt of blanks.

[Ozymandias Ghost]

They’re firing blanks. That plug in the muzzle is a BFA (Blank Firing Adapter). It is required for both safety and to increase gas pressure to allow the weapon to cycle properly w/blank ammunition.

Link: http://store.armyproperty.com/products/blank-firing-adapter-bfa-red-for-m240-series-machine-gun.html

[ProtectOurFreedom]

Pretty crappy Photoshop job.

Editor: “Quick! We need a photo of the evil military firing weapons for an article we are running.”
Editor 10 minutes later: “No, that sucks. It needs to be more dramatic. Show me a lot of fire coming out of the killing machine.”
Editor 5 minutes later: “Yeah, that’s it. Perfect. Shows what a death machine it is. I like it. Run it.”

[Bonemaker]

Blanks