#CasedTelescopedSmallArmsSystem

One thing that seems apparent from the ARDEC presentation on the CTSAS program is the excessive capability and weight of the 6.5mm CT ammunition, as well as its use of lead-cored projectiles as opposed to more modern (and less dense) EPR-type projectiles. Further, the 6.5mm configuration explicitly uses the same case as the 7.62mm CT round, to allow for shorter development times. These facts together indicate that the 6.5mm CT round demonstrated in the ARDEC presentation is not well optimized for minimum weight. For this post, we’ll create an estimate of a new, lighter round that still should be powerful enough to replace both 5.56mm and 7.62mm as a universal caliber. As mentioned in the previous post, we’ll call it the “LW 6.5mm CT” to differentiate it from ARDEC’s 6.5mm CT round.

Recently, I wrote an editorial regarding the LSAT/CTSAS team’s NDIA presentation on their 6.5mm cased telescoped carbine and machine gun concepts. There was a lot to say about the history of Army programs and the pitfalls facing that team, but today I want to get down to brass tacks and explore the weight savings and/or penalty of issuing to the infantry platoon the 6.5mm CT cartridge Phillips’ team proposed. Like in my November of 2013 article on the general purpose cartridge concept, I will be using the loads reported in the paper The Modern Warrior’s Combat Load, released in 2003. That paper is a little dated, unfortunately, but it’s the most comprehensive survey of the platoon’s loadout of which I am aware.