Agreed with Bruce. My rifle of choice has always been a LE. The basics of LE after shooting care starts with a litre or more boiling water down the barrel. Let it stand muzzle down, dries quickly because the boiling water heats the metal, which of course dries off the water. Then clean and oil. Barrels are still shiny with good rifling after decades of use.

Shot literally thousands of corrosive cordite military ammo.

Anecdote. One of the guys in my shooting club had a Long Branch No 4 with a dull bore. Couldn't get it to shine no matter what he did. We had 'unlimited' 303 still [was about 1985]; he and a couple of fellow shooters fired a couple hundred rounds quickly through that LB one afternoon, he called me to come see/hear. The oil in the wood crackled like fat frying, couldn't hold the fore end it was too hot. When it cooled down, some time later in the day, he was quite excited, showed me the bore - almost blinded by the bright shiny lands and grooves! The dull bore was no more and didn't return! And that was before cleaning.