Treso touch hole liners are made from the same tough and erosion resistant Ampco alloy as the Treso nipples. Flash hole is .0625 diameter. The Treso flint touch hole liner is installed in a 1/4×28 thread in the side of the barrel with a wrench (see information below for specific instructions on installation). We recommend anti-seize material be coated on nipple and touch hole liner threads to make them more easily removable.
Installation Instructions — Wrench Model: Drill and tap the barrel for 1/4×28 thread at the proper location at the breech. Slightly countersink hole with an 82 degree countersink. Install and note if any liner protrudes into the barrel bore; if it does, shorten inside end to appropriate length. Tighten liner securely with standard rifle nipple wrench and file flush with outside of barrel. To remove, enlarge touch hole and remove with broken bolt (easy out) extractor.