this is my r93 after a good soaking yesterday, and a quick washdown with the hose to get the mud and blood off. it was fired and the inside of the barrell will not be touched. i gave the mod a quick squirt of wd40 on the outside and the screwcut gets a wipe of molyncote grease, but thats it, definately no wd40 on the inside of the mod as i've found it affects accuracy.
if i choose to clean the barrell, i use hoppes copper solvent and patches, no brush. i have learnt how to clean it so that 1st shot out is bang on, but i rarely clean it now, as with both my .243 and .308 r93's i have found there is no need. i never oil the barrells.
if i do clean them i always fire a test shot at paper first but with these rifles, it has never been off zero after a clean, as long as you get all of the solvent out - this can be done by repeated dry patching or with some meths, as i have just learnt from this site.
happy cleaning