I edited my previous post.





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I once bought an old Kettner hammer drilling at Jaquas for almost nothing. The 9.3 rifle barrel looked like a third shotgun barrel with no visible rifling. (This was a 9.3x72 which was always loaded with lead bullets.) I plugged the barrel with a rubber cork, stood it on the muzzle and poured it full of a lead removal solvent. Left it about a day, emptied and cleaned, and the bore was literally pristine. That ws the most leaded barrel I had ever seen.

With the shotgun, the 45 pads would seem to be a good bet. That is one of the things they are designed to do.

You might try a Lewis Lead Remover.They are used for hand guns but you might be able to attach to a longer rod for your application.Brownells has them in 41 caliber.Im sure other shooting supply centers carry them also.

In this day and age are we really talking lead, not wad plastic build-up?

I "clogged" my barrels with plastic years ago from Skeet shooting but the lead fouling I referred to earlier in this thread was from previous owners shooting shells produced before the plastic shot cups were introduced.
The plastic was relatively easy to remove, though it was a repetitious job with a plastic solvent and a repeated bore brushing... but my bore brush really got clogged with plastic...





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Try a Frontier 45 pad or a copper wool pad wrapped around a bronze brush + oil. Hand scrub or chuck the rod in a variable drill.

This little Belgium 410 was made in 1931 and hasn't been shot in many many years. There was virtually no plastic build up but plenty of lead. I shipped the barrels to Skeet's Monday and Dean confirmed today the build up was lead. He will work on getting the bores clean.