Abstract: A composition comprising a mixture of coarse and fine iron powder and at least one densification enhancing additive for economically producing metal injection molding components.

Abstract: A sight for a gun includes a transparent, substantially cubic, glass body having a front, a rear, and peripheral surfaces including a top, a bottom, a right side and a left side which are opaque and matte. A semi-reflective surface within the body extends from the top to the bottom at a diagonal to the front. Light from a light emitting diode and reticle negative on a the bottom surface is collimated by a collimating mirror with an F/# between 0.6 and 2.0 and reticle negative on the top surface. Light from a target may pass through the front of the transparent body and exit the rear, and light from the light source may be imaged by the reticle negative, pass through the semi-reflective mirror, be reflected and collimated by the collimating mirror and reflected out of the rear by the semi-reflective mirror as an aimpoint pattern that intermixes with light from the target and the light source.

Abstract: A gas sealing device for a gas-operated firearm having a piston with a land surface positioned between a lateral flange and a peripheral rib, and a piston seal radially mounted on the land surface and positioned between the lateral flange and the peripheral rib. In operation, the piston and the piston seal can remain interlocked, but still operational so that upon firing, the piston is deflected towards the magazine tube due to the force applied by the piston seal. The piston seal exerts the force on the piston due to the impingement of a propellant gas charge on the piston seal.