We put .223 on the barrel as that is what is recommended for best results - match grade .223 ammunition.
To me this seems like a fundamentally flawed practice. I would prefer to have my barrel stamped with the actual chamber rather than preferred ammo. Although the chamber can withstand higher pressures than what's stamped on the barrel (.223) you are somewhat misleading the end user. Why not just stamp it as it is and tell the consumer that you recommend match grade .223 for best results? The whole topic of " match grade" in itself is a can of worms and is grossly over used and poorly defined term.
This really isn't a HUGE deal to me, but just seems a bit odd. Certainly safer than the other way around which might be a possibility (however remote) if you have a process for labeling something different than what it actually is.