individual non-lethal weapons system

In the US military one of the key requirements for non-lethal systems seems to be the ability to work from 5 to 400 meters.

One of the patents MST referred to earlier this year was related to selectable velocity.

Patent Serial No. 12/273702 is important for less lethal and for large calibre weapons. It provides patent protection for systems that provide selectable kinetic energy (selectable velocity) using externally arranged propellant chambers. This is particularly important in multiple range less lethal weapon systems where you need to hit targets at different ranges with the same force, and other situations where the trajectory arc as well as range needs to be controlled.

Anyone know what 'externally arranged propellant chambers' means? IS this just referring to the fact MST ammo doesn't have its propellant inside a cartridge?

Also, anyone know if MST responded to the following:

https://www.fbo.gov/index?s=opportunity&mode=form&id=80bd69796476fcbb3366925d61992c1b&tab=core&tabmode=list&=

Maybe whoever wins the MPM-NLWS contract could use the same launching tubes, fire control electronics and ammo in an individual 40mm non-lethal weapon system!!