M99 Stanchion

The M99 "Stanchion" is almost certainly the sniper rifle being fired by Avery Johnson (presumably him) on page 122 in the Halo Graphic Novel. In the upper left hand side of the page, a small green box can be viewed containing what appears to be a company's seal, as well as the title and description of the weapon. At first glance, the rifle being fired by the black man looks similair to an S2-AM sniper rifle or it's cousins, but it looks distinct in the fact that it has no visible muzzle brake or a flash suppressor mounted to it's barrel.

The caliber for the weapon is actually quite small, being only 5.4mm, or .21 caliber, the gun may very well be less potent that the much larger 14.5mm cartridges utilized in most UNSC sniper rifles. SASR might stand for "semi-automatic sniper rifle", but this is unconfirmed. Other than the description and picture of the rifle, nothing else is yet known about this weapon.