There are myriad excellent substitutes for oil as a lubricant on firearms and trust the mule-headed military brass to be the last in the world to be aware of it. Did they think Iraq was NOT going to be dusty?
One such is trade-named "dri-kote" which is does not attract dust and is an excellent colorless lubricant. One good application of it and dust and grit just bounce off of those tightly toleranced parts. However, if today's army is anything like my training outfit, a soldier would be court-martialed for using it.
I would expect that most of the weapons problems can be traced back to bureauocratic paralysis and lack of professionalism in the upper echelons of the military services.
Today I was at the range shooting a 1903-A3 and a Remington 1917 Enfield. Both in 30-06. No problem on knockdown or long-range power. THe 1903-A3 has the prettiest trigger pull. You pull back until it catches. Any increase in trigger force will cause the gun to fire. It is like this every time. I just wish it had a 1903-A1 rear sight instead of the 1903-A3.