Greetings again,
From what I have read the hot or boiling water is essential as the corrosion will continue in spite of being oiled. The boiling water is needed the same day as the rifle is fired. After the move from black powder to smokeless the problems with corrosion started. Originally this was blamed on the smokeless powder but investigation showed it was the chlorate primers. The black powder fouling did protect the barrels and was cleaned out much more frequently. The cordite propellant is also quite erosive and this is part of the reason for the long and loose throats on most Lee Enfields.
Regards Grandpamac.
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