The PSA CHF Nitride barrel is believed to be made in house by PSA, (which since PSA is part of a conglomerate, may not be known by most of us outsiders. It is believed that these barrels are made in the mid-west, or west coast, although at this time that is pure speculation as there are many Cold Hammer Forges around the world and North America. Some of those include, FN Herstal, Colt Canada (diemaco), Daniel Defense, Ruger, Arsenal (Bulgaria), Styer (Austria), Remington, Knights Armament, etc. I feel that the key is to find who’s making the CHF Nitride barrels, and you’ll know what company is making them for PSA, be it a conglomerate member or not. Because PSA’s description of these state “Made in the USA” it tells me it has to be a domestic manufacturer. These barrels are listed as being made from 4150V Chrome Moly Steel, and can come in a variety of Gas systems, profiles, and twists. As with all PSA barrels, they have a M4 barrel extension. , 3.)The PSA Freedom Tier. a.PSA Freedom Line – Stainless Steel. b.PSA Freedom Line – Nitride or phosphate coated. 4.)The PSA Unmarked/PTAC Tier. a.PSA unmarked line – Nitride or phosphate coated. b.PTAC marked or unmarked – Nitride or phosphate coated. 1.) The PSA Top Tier: A.) The top dog in the PSA line is the CHF CL/MP barrel., This is the classic PSA trippity-trappity-gatcha-switcheroo. As soon as I buy gen1 of something, thats when they announce the new and improved gen2 that includes that one feature I really wish gen1 had. They'll come out with a new product. I say I'm gonna wait till they start offering that product with X feature..