Corrosive salts are a
first cousin to table salt, which loves to dissolve in plain ol' tap water.
Because of that here's what I do, YMMV.
I take a small pump bottle (4oz about 2 1/2" long by 1/2" wide) filled with water to the range with me. I wet 3 patches & run them through the bore, followed by 3 dry patches & an oily one. I do this while the barrel is still warm from firing. Then I take the gun home & clean normally
the same day. I finish up with an oily mop & check the next day.
*note: My cleaner is water-based & I clean thoroughly, this may effect the final process, but I've yet to have any rust in 45 years of shooting corrosive .303 British.
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Allan Quatermain: “Automatic rifles. Who in God's name has automatic rifles”?
Elderly Hunter: “That's dashed unsporting. Probably Belgium.”