THROAT EROSION GAUGE ARA- MOR

Instant, At-A-Glance Barrel Throat Wear Indicator Gives accurate, comparative readings on actual barrel throat erosion for all M1, M14 and M1A .30-06 and 7.62mm Nato, High Power Service Rifles. Insert in empty chamber and take reading every 1,000 rounds to accurately measure and track barrel throat erosion. Big Book Catalog, Issue:72, Page:468