Many years ago, whilst a member on here, I made many pull throughs and either gave them away, or took a small price once I'd increased the quality of the components.
They were very popular.


I used 80lb conger trace (plastic-coated steel wire) a length of twice the length of the barrel, plus 10 inches.
Loop it so that both loose ends are together, then pinch the looped end so that it forms a 'U' shape.
The handle can be one of two choices; wood or metal (as plastic tube is rarely strong enough). Take a pice of wooden dowel, or metal tube, the width of your hand and drill a small 1/8th hole in the centre of it. This is where the wire will enter the handle.
Push the 2 loose ends of the wire in through the hole and out the other side. If using wooden dowel you can wind the loose ends once around the wood before crimping the wire ends together. Finish with electrician's tape wound around the dowel.
If using metal tube, you can apply a plastic bead onto the two loose ends before crimping them.
Once crimped, just pull the crimped wire ends back into the handle.

Ready easy, and only takes 15 minutes.

Other ideas I heard were to uses trimmer line longer than the barrel, and melt one end into a blob that is plenty small enough to pass through the bore with a patch on it.
This idea means less construction, but getting the size of the blob is critical, and not easy.

Go with the wired option and use Parker Hale 009 as your cleaner. A few drops on a cotton patch is all you need to shift the crud.