Bullet comprising a compacted mixture of copper powder
A bullet comprising a compacted mixture of copper powder comprising particles that are physically bonded to each other to form a cohesive and ductile microstructure is disclosed. Methods of making such a bullet through powdered metallurgy techniques, which provide sufficient properties to allow the bullet to be loaded into a cartridge and crimped without fracture are also disclosed. Such bullets have sufficient strength to maintain their integrity during firing but may fragment upon impact and can be formulated lead-free.
1. A bullet comprising a compacted mixture of a single metal powder comprising at least 98.5% by weight of copper, wherein the single metal powder comprises partially sintered copper particles that are physically bonded to each other via metallic bonds to form a cohesive and ductile microstructure that is substantially free of intermetallic alloys.
2. The bullet of claim 1 , which exhibits a density ranging from 7.0 to 8.2 g/cc.
3. The bullet of claim 1 , further comprising an admixed lubricant.
4. The bullet of claim 3 , wherein said lubricant comprises at least one chosen from molybdenum disulfide, lithium stearate, zinc stearate, carbon, synthetic wax, and a polymer.
5. The bullet of claim 4 , wherein the synthetic wax comprises N,N′ Ethylene Bis-Stearamide or N,N′ Distearoylethylenediamine.
6. The bullet of claim 1 , wherein the bullet is lead free.
7. The bullet of claim 1 , wherein the bullet further comprises at least one component chosen from a heel, driving band, nose, ogive and a meplat.
8. The bullet of claim 7 , wherein the heel further comprises a concave base to aid in compaction in the nose of the projectile.
9. The bullet of claim 7 , further comprising a fixed-fill nose or ogive section.
10. The bullet of claim 1 , which further comprises at least one cannelure groove, a tipped point, a hollow point, boat-tailed, ring, or groove.
11. The bullet of claim 1 , wherein the single metal powder comprises at least 99.5% by weight of copper.