flash hider / muzzle brake threaded for suppressor

[TacoJockey]

I'm looking at building a 300 Blackout upper for my bullet buttoned AR and need to know if its legal to have a flash hider / muzzle brake that has threads for a suppressor. I know threaded rifle barrels are legal but need to know if that extends to muzzle devices themselves. It just seems like all the muzzle devices I like also have suppressor threads.

[crackerman]

You should be fine

[Cokebottle]

Perfectly legal on any rifle.
Threaded barrel is not an SB23 "feature" on a rifle.

Threaded barrel is an SB23 feature on a handgun.