I shoot .38 spl. out of my 66-1 because I get the ammo for free.

Unfortunately it also leaves debris and fouling in the cylinder. What size bore brush is the best fit to clean that out?

Go to Brownell's web site and do a search for ".38 chamber brush".

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"I also cook."

FINDING .40 S&W. (10MM.) or .41 cal. bronze bristles & vigorosly scrubbing with OLE' Hoppe's #9; is not a mistake.You wil find cleaning,using these....... is easier,and you will be happy . * Remember,brush =one size bigger than the bore size

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Dino in Pittsburgh's Rat Pack

I have used nothing but .375 rifle brushes for the past 30 years or so.

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Gunsmithing since 1961

40 cal/10mm drizzled with Hoppe's or Ed's Red and chucked up in the power drill works for me when cleaning a neglected 357 cylinder that has shot a lot of 38 spcl.

Class III

I use Brownell's standard line bronze brushes but get them in the RIFLE length. IF the leading is a bit more than usual I'll use the Brownell's CHAMBER RIFLE brush which is slightly stiffer and tighter. It's rare that lead is present after that, but if it is the Lewis Lead Remover is the go-to. Rifle length gives you a bit more cleaning power but shouldn't be used in a revolver's barrel because it will not make it through and back without bending the bristles. In a cylinder charge hole or auto-loader barrel it will be just fine, just push all the way through before reversing direction.

Chief38