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Same barrel, same washer, same hider. Absolutely no problem putting it back on. I've done it many times over the years. Change the hider or the barrel combo and a new washer may be needed.
I've reused the crush washer with no problem. I bought a new one to put on, but when I did, the hider would not line up to where it should have, I would have had to crank on the hider way to hard, so I just put on the old one and it was fine.
That's what I like about Smith Vortex flash hiders--No indexing or crush washer needed. Just turn it on, tighten it up, and go!