I would think that the use of triple base propellants in hand-held weapons, such as assault rifles or pistols, would be greatly beneficial as its use would remove the muzzle flash. Also, it would decrease wear-and-tear on the weapon itself, I would think.
I have found some people saying that triple base propellants are only used in heavy weaponry (such as for tanks or naval vessels) due to teh scarcity of nitroguanidinium https://fas.org/man/dod-101/sys/land/bullets3.htm . Does anyone know why, generally, only single base propellants are used for assault rifles and pistols?