60mm (M27), 81mm (M24 and M28), 120mm (M31) Mortar Tail Fins

In support of the Project Manager, Combat Ammunition Systems (PM CAS), the U.S. Army Contracting Command-New Jersey (ACC-NJ), located at Picatinny Arsenal, NJ, hereby issues a Request for Proposal (RFP) for the manufacture, test, packaging, and delivery of the 60mm (M27),81mm (M24 and M28), 120mm (M31) Mortar Tail Fins. These Tail Fins are components of the 60mm, 81mm and 120mm Mortar Cartridge variants, High Explosive (HE), Full Range Practice Cartridge (FRPC), and Illumination and Smoke items.

M27 Mortar Fin: The M27 Mortar Tail Fin Assemblies support the 60mm family of HE, Training, Smoke and Illumination Mortar Cartridge Programs. The one-piece M27 Fin is 5.40 inch (in.) long and 2.375 in. in diameter at the fin blades. The fin is made of 2014-T65 or 6070- T6 aluminum (Spec. ASTM B221). Six (6) individual blades are extruded at the end of the boom. Each blade is precisely canted at 5 degrees. The center of the fin is hollow and threaded at the end so the M702 Ignition Cartridge can be inserted and secured in the fin. Flash holes are drilled in the hollow section of the boom to vent gas and flame from the M702 Ignition Cartridge.

M24 Mortar Fin: The M24 Mortar Tail Fin Assemblies support the 81mm family of HE, Training, Smoke and Illumination Mortar Cartridge Programs. The assemblies are a two-piece design (fin component pressed fit onto the housing component). The M24 assembly is 7.4 in. long and 3 in. in diameter at the fin blades. The M24 fin components are made from aluminum Alloy (Spec ASTM B221, hollow extrusions not permitted) and the M24 housing components from Aluminum 7075-T6 (Die Forging, Spec ASTM B247 or Rod, Spec ASTM B211or B221). Both the M24 fin and housing components are also anodized (Finish 7.2.1 of MIL-STD-171, shall withstand a 336-hour salt spray test for First Article Parts and 96-hour Salt Spray Test during production). Six (6) individual blades are extruded at the end of the boom. Each blade is precisely canted at 5 degrees, 17 minutes. The center of the M24 fin component is hollow and threaded at the end so that the M299 ignition cartridge can be inserted and secured in the fin. Flash holes are drilled in the hollow section of the boom to vent gas and flame from the M299 Ignition Cartridge.

M28 Mortar Fin: The M28 Mortar Tail Fin Assemblies support the 81mm family of HE, Training, Smoke and Illumination Mortar Cartridge Programs. The assemblies are a two-piece design (fin component pressed fit onto the housing component). The M28 Assembly is 8.545 in. long and 3.150 in. in diameter at the fin blades. The M28 fin components are made from Extruded Aluminum Allow 2014-T4 (Spec ASTM B221) and the M28 housing components from Aluminum Alloy Bar 7075-TT76 (Spec ASTM B221). Both the M28 fin and housing components are also anodized (finish 7.2.1 of MIL-STD-171, shall withstand a 336-hour salt spray test for first article parts and 96-hour Salt Spray Test during production). Six (6) individual blades are extruded at the end of the boom. Each blade is precisely canted at 4 degrees, 46 minutes. The center of the M28 fin component is hollow and threaded at the end so that the M752A1 Ignition cartridge can be inserted and secured in the fin. Flash holes are drilled in the hollow section of the boom to vent gas and flame from the M752A1 Ignition Cartridge.

M31 Mortar Fin: The M31 Mortar Tail Fin Assemblies support the 120mm family of mortar items. The 120mm M31 Tail Fin is an eight-bladed two-piece (fin and tube) fin assembly approximately 9.25 inches long and 4.75 inches in diameter at the blades. The fin component is machined from an extrusion of 2024-T8511 aluminum, and the tube is machined from a seamless extruded tube, extruded rod or alloy rod rolled 2024-T3511 aluminum. The tube center is hollowed to allow insertion of an ignition cartridge. The 120mm M31 Tail Fin assembly is anodized (Finish 7.2.1 of MIL-STD-171, shall withstand a 336-hour salt spray test for first article parts and 96-hour Salt Spray Test during production).