Nothing wrong with Cerakote on externals. Don’t want it on any internals. Nitride is very durable, (mostly as durable as your metal),but mainly only in black….and will show wear over time. Cerakote can be touched up. Birdsong is extremely slick and practically rust proof….but it will wear faster than nitride. Either would still last an average Hunter a lifetime, I’d imagine.
Is Birdsong still is business? I emailed them quite some time ago and didn't receive a response.
