Yeah, I remember you telling me to tell my brother that. He's pretty good when it comes to keeping his guns cleaned and oiled.
It's actually easier to clean that way. We figured this out right away, not just because our NCOs kept telling us to, and weapons cleaning was a regular activity, but we used blanks frequently and they create a mess in the barrel and bolt.
I was in a Weapons Company so we would eventually end up cleaning personal and crew-served weapons at the armory to be inspected and turned in etc.
The Heavy machine gunners (0331) had a few tricks with hot water and solvent etc, and we quickly adopted that ourselves. But the oil they issued us ("CWP") was total crap! So we used the CWP for light use under "supervised conditions" but we used normal light weapons oils otherwise. It was cheap and we found we could clean our weapons more quickly and efficiently.