While you can, it's generally not a good idea unless you absolutely got drenched/rained on, you swam in ocean water, or got mud and fine gritty crap in the action (both the National Match M14 and the M21 / M25).
On military teams we generally did it at the end of the season to clean out all the yucky stuff that had built up, and for the armorers to check the bedding. If the bedding was chewed-up or loose it got skim-bedded for another season. Typically two or three seasons / years and you got a new barrel.
Individual shooter was responsible for reaming his own gas plug, cleaning the gas piston and cylinder, and ensuring the flash suppressor was tight and not flame-cut through the end of each slot. Grease for the bolt and cam slots, roller, recoil spring, and operating rod and guide (usually with long applicators).
The 30-cal rifles (M1 and M14) didn't have as many small bits to lose like the match M16, and operator maintenance generally didn't require removing the action from the stock