Selling a Faxon Firearms AR15 barrel. 16" mid-length has system. 4150 with a 1 : 8 twist rate. This one uses Faxon's Gunner profile. I used this for a rifle for my wife. It's super lightweight. She hasn't shot it in over 5 years and I decided to cannibalize her upper receiver for something else. The barrel has less than 200 rounds through it.