“Wars may be fought with weapons, but they are won by men.” George S. Patton is right but the men and women who fight these wars are only as good as their equipment and armament they use, specifically their weapons and ammunition.
The United States Army’s weapon of choice for soldiers on the ground has been the M-4 Carbine for over 20 years. Since the M-4 is easily maintained and comparatively cheaper than other alternatives, I doubt the Department of Defense would waste funds trying to find an alternative within the next decade. However, ammunition has been advancing and improving significantly over the past several years.
In September of this year, I had the chance to visit the Lake City Army Ammunition Plant (LCAAP) in Lake City, MO. This plant manufactures and distributes approximately 90% of the ammunition used by the Army. While I was there I toured the cartridge manufacturing facilities. Bill Melton and his staff explained each phase of the cartridge manufacturing process and the different procedures that went into developing tracer rounds, armor-piercing rounds, and others types of cartridges. Throughout the tour I could not help but think about how far ammunition has advanced.
From musket balls, that are inaccurate if shooting at something more than 50 meters away, to the destructive anti-material .50 caliber Raufoss round, which is an explosive round with a delayed detonation until initial target penetration to cause damage inside the target for maximum anti-personnel and fire start effect, ammunition has, without a doubt, advanced over time. The most recent improvement being the development of a hardened steel penetrator for 5.56mm and 7.62mm rounds. Unlike previous rounds, the hardened steel penetrator is fully exposed rather than hidden by soft copper. The 5.56mm M855A1 Enhanced Performance Round also travels at a higher velocity which allows soldiers to penetrate tougher battlefield barriers up to approximately 400 meters. This surpasses the current M855 5.56mm round by over 200 meters. The M855A1 Enhanced Performance Round is a significantly improved 5.56mm round that provides excellent soft target consistency and an even better hard target performance. This round increases Soldier effectiveness at extended ranges with greater accuracy by a considerable amount. The most impressive feature of this round is that it does all of this without increasing the amount of weight placed on the Soldier. The idea that cartridge improvements can be made without increasing the weight of the round itself has left Soldiers to question if ammunition can provide the same destructive effects and weigh less, thus allowing them to carry more ammunition or other supplies.
From musket balls, … to the destructive anti-material .50 caliber Raufoss round, … ammunition has, without a doubt, advanced over time.
Well, the engineers and innovators of Orbital Army Technologies as LCAAP have heard and responded to the requests of soldiers returning from Afghanistan and other combat zones. A new case for ammunition is in the early stages of development at Lake City. Rather than brass cased ammunition, cartridges will have new lightweight polymer casing. The switch from brass to polymer will reduce the weight of ammunition by approximately 20-30% but still have the desired effect on the enemy. However, the switch also comes with a number of complications that need solved before it is implemented. One of these complications is the use of polymer cased 7.62mm belts for the M240B machine gun. The current M13 links grip the polymer casing so tightly that the links shear polymer off the case. The amount of force required to de-link a round from a link, the stripping force, is set at 8.5-18 pounds. This standard is an Army regulation for ammunition used in training and operations. The current M13 link with the polymer cased ammunition has a stripping force in excess of 20 pounds. This causes problems when firing the weapon system because the round does not eject from the links. However, PCP Ammunitions out of Florida have developed a modified link that meets the standards of the Army. The modified links brings the average stripping force down to approximately 9 pounds, which is on the lower end of the spectrum. Although there have been several innovations regarding lightweight polymer cased ammunition, they are not scheduled to be mass produced until 2022.
Although the weapon system may not be changing, the ammunition used by the weapon system is. The Lake City Army Ammunition Plant plays a key role in developing new ammunition that will allow our soldiers to complete their mission overseas. With innovation such as the Enhanced Performance Round, soldiers will be able to eliminate enemy targets while minimizing the amount of danger they put themselves in. This innovation will also lead to an increased level of battlefield effectiveness by allowing our soldiers on the ground to engage targets at further distances while carrying more ammunition or other equipment if necessary. The ever changing world of ammunition is essential to the safety and effectiveness of the combat troops on the ground who are defending America’s freedom.
[U.S. Army photo by Sgt. Roland Hale]
While the issue of polymer cased small arms ammunition is often purported to be a significant benefit for infantry, the issue of lighter weight is applicable only when a basic loadout of ammunition is carried. As a former Marine Corps 0331 – Machine gunner, who was assigned ‘Da Pig” [M-60 machinegun], one often opted to forgo other items in favor of more ammunition. The trend since WW2 is to pack on more and more weight in the form of armor and additional mandated gear onto the foot soldier, not to decrease it. Adoption of polymer ammo will make no significant reduction in gross weight.
Another factor not addressed is the necessary national infrastructure to support production. Since polymers are manufactured from hydrocarbon gas liquids (HGL) and natural gas, can the U.S. maintain sufficient stocks of these multi-use petroleum products for production of ammunition and not divert LPG and HGL from required uses such as electrical production, heating, and other industrial processes that require such fuels. Many modern synthetic lubricants and petroleum specialty chemicals use these oil stocks in their production and during wartime production levels, would directly compete with polymer production and other previously mentioned demands.
Copper production, roughly 85% of raw brass alloy, is relatively steady within the U.S. and within the State of Arizona, who traditionally is the nation’s greatest copper producer. The great benefit of brass metal is that it is a proven system, easy to produce in large quantities, and requires only basic earth moving machinery to remove the geologic overburden to access the copper bearing ore. Zinc production is stable and subject to parameters similar to copper.
Brass cartridge cases require multistep drawing and forming steps to produce a finished product and polymer cases would require simple injection-molding. Polymer cased ammunition would be less susceptible to denting, case corrosion, galvanic corrosion in links or chambers, and have reduced tare weight in shipping and handling. This gives the benefit to polymer. Brass cased ammunition has higher shear strength, a lower Young’s modulus index, will obturate under peak pressure loading, and then contract well to facilitate extraction and ejection. Polymer has trouble meeting this critical parameter under high temperature demands of a weapon with a high cyclic rate or constant demand of sustained fire. Another issue is “cookoff” and resistance to high thermal degradation in use. Torn cartridge rims and case separation in weapons with excessive headspace are a significant concern to end-users. Will a separated polymer case partially or wholly melt in the overheated chamber of a M249 and can such a stoppage be as easily remedied as it can now with brass cased ammunition? Where are the testing results and empirical evidence in support of such a move?
Brass can be easily recycled after use in training or operational use and returned into new use. Polymer can be recycled, although not as easily as brass. I do not know if substrate infused polymer can be recycled.
Another factor to consider is that the DoD has been searching for the follow-on system to the M16 and its’ derivatives. The XM-8, the SCAR-L, the Heckler und Koch G11 caseless ammunition firing rifle and the G36, and others have been examined and tested for possible adoption. The 5.56x45mm cartridge itself is still being argued over and Afghanistan operations has shown a need for a longer ranging ammunition [hence the use of the SCAR-H by SOCOM]. The warfighters in the Army and the Marines seemingly want a new rifle and the M16 system has some serious issues [direct gas impingement] that should be addressed.
If they could make a bullet with a plastic explosive and detonator there would be no need for heavy shells just a strong well designed gun. There would also be no evidence of shell casings left by the soldier. The tip of the bullet would need to be made out of something that won’t deform under the rapid explosion of RDX and could potentially be made lighter due to the faster accelerant. Not having to eject casings also simplifies the gun making it lighter.
Thank you for your comments and critiques. I appreciate them greatly. A lot of the unaddressed material that M Schweren discusses was left out of the piece because I was trying to keep it as brief as possible while still making the focus on what is currently happening with respect to ammunition. I recently finished a technical report for the implementation of Lightweight Polymer Cased Ammunition in the Loading, Assembly, and Packaging process. The primary concern as voiced by the faculty and leadership at Lake City was the stripping force required to de-link the round from the links. However, this article is derived from my focus on a specific area of the cartridge manufacturing process and does not take into account a number of factors that could affect the implementation of polymer.
Another type of cartridge in development currently is a caseless round. According to the information and schematics from PCP Ammunitions in Florida, once the round has been fired, there is no leftover shells or cartridges. Both of these developments in ammunition are in their infancy. In another year or so, the amount of information available on this topic will expand and increase in variety.
Again, thank you for the comments and I appreciate the feedback.