The profile of these barrels are for Bulgarian rifles. Trunnion diameter is .867"
Made from 4150 1-8 Twist Chrome Moly steel and black nitrided inside and out , Gas Port drilled. The handguard retainer slots and extractor clearance cut has also been done on these barrels.
Made in the USA and Stamped for 922r Compliance.
This item is made in the United States and counts as a 922r compliant part.