Flash Hiders while hunting?

[NINEX19]

OK, a little help would be appreciated. I have searched the forum and the WDFW 2015 regs. and I can not seem to find a firm answer.
I recently got a .308 with a threaded barrel, but does not have a thread protector. I would like to take it elk hunting this year. There is a flash hider on it. I don't want to take it off and leave exposed threads. Knowing all of the goofy regulations in this state it would not surprise me if there was a regulation against hunting with a flash hider attached (for whatever reason).

So, can anyone point to any regulation that says hunting big game with a flash hider is illegal in this state?

[JimmyHoffa]

It's legal. 

[Stein]

You can have anything on there except a suppressor.

[JimmyHoffa]

You can have anything on there except a suppressor.

When did that change?

[Stein]

You can have anything on there except a suppressor.

When did that change?

It's been the same as long as I have been hunting in WA (I think?) but that is only 5 years.

[Yondering]

I've never seen a reg against hunting with a suppressor. Post a link.

Pretty sure they are legal.

[Bango skank]

You can have anything on there except a suppressor.

Suppressors are legal to hunt with here