Possum Hollow Bore Guide group to suit the bolt diameters approximately 16.0mm. Please follow the “3 step” instructions here to help choose the correct bore Whether you are cleaning a $400 Savage, or a $4000 custom 6mm BR Benchrest rig, you NEED a bore guide to protect your barrel from cleaning-rod damage. The Universal Bore Guide offers an easier and safer clean by aiding in the alignment of your cleaning rod with the barrel of your firearm.For rifles chambered in 308, 30BR, 7mm-08 and 7mm BR. This Rod Guide will fit any action with a bolt diameter between .695" and .700". Cleaning Rod Guides. Refine By. Showing 6 results. Sort by. Featured, Newest, Best Selling, A - Z, Z - A, Reviews, Price: Low to High, Price: High to Low Most gunsmiths agree that more .22lr barrels are ruined from improper cleaning than from actually being shot out. These guides fit into the raceway of the Bore guides are essential for cleaning. A good one will ensure that you do not ruin a barrel with poor cleaning habits. Most gunsmiths agree that more .22lr Adjustable Bolt Action Rifle Bore Guides The Pro-Shot "Stopper Series" of Bore Guides provides ultimate protection to the bore throat and keeps cleaning