I’ve got one of their 16” 1:8” .223 Wyldie barrels from back around ‘16 and it was disappointing with heavies, but hammers with 65 grains and down.
Gave up on 75’s and just stuck with Hornady 55 and 53’s (evil with 53 V maxes).
Can’t complain. If I wanted to run heavies, I shoulda bought a 1:7”.