Advanced Material Gun Barrel

Improvement to machine gun type automatic weapons is limited by the wear and erosion rates on current gun barrel materials. The technology exists for increasing rates of fire and muzzle velocities with new projectiles. These advanced projectiles develop significantly higher flame temperatures and bore pressures. Gun barrel erosion is accelerated by the combination of the high temperature gas erosion and the friction between the projectile and liner. Significant improvements to accuracy and lethality can be realized with improved gun barrels that withstand these advanced projectiles. The proposed program combines the experience of Saco Defense, Inc. and Foster-Millers's unique gun barrel design concept to produce a structure capable of withstanding the severe erosive environment, providing for greatly enhanced thermal conductivity both through and along the barrel axis. A ceramic liner will be used at the bore with a reinforcing carbon-carbon (C-C) sleeve. The C-C sleeve will be embedded with radial P100 graphite fibers using Foster-Miller proprietary technology. P100 fibers exhibit among the highest thermal conductivities known and will be used along the barrel axis as well. The unique properties of C-C materials to increase liner compression with temperature, because of the negative CTE, will overcome a common problem encountered with metallic sleeves. The program will entail design, fabrication, and testing of a typical liner/sleeve assembly in Phase I. The thermally induced strains, confirmed in Phase I, will form the basis of a Phase II program which will include rapid fire testing of the gun barrel.