A bore mop is not a scrubbing tool. Its job is to carry oil evenly down a clean bore, or to dry one out after solvent — the cutting work belongs to a brush and the final pass to a jag and patch.
Wool or cotton. Wool holds more oil and is the traditional choice for laying up a gun over the close season. Cotton mops shed less and suit drying after a wet solvent clean. Both are consumable — once a mop has picked up grit or carbon it will drag that back down the bore, so retire it rather than washing it.
Check the thread before you order. Mop threads are not universal. Parker-Hale rods use their own thread and Bisley's wool mops are cut to suit it; Tipton, Napier and Birchwood Casey mops are supplied for their own rod systems. Match the mop to the rod you actually own, or add the correct adaptor.
Sizing. Rifle mops run from .17 through the common .22 to .270 group; shotgun mops are gauge-specific, 12 bore being the bulk of the range. A mop wants to be a firm push, not a fight — an oversized one will stick.
Related: Cleaning Kits, Cleaning Rods, Bore Brushes, Cleaning Sprays, Maintenance Stations.
