Unpinning a pinned 14.5" once I go down the SBR route - opinions desired

General Firearms NFA
1

Here is my current setup
LMT Defender lower
14.5” LMT upper with Vortex flash hider pinned by ADCO.

My plans:
Same lower SBR’d
9” AAC 300 BLK upper + AAC 7.62 SDN-6 suppressor.

Question:
Once I get the stamp back on the SBR would you:

  1. Leave the 5.56 upper alone and not worry about suppression.
  2. Send it back to ADCO and have the flash hider unpinned so I could swap out with an AAC 51T flash hider so that I can use the can on multiple calibers.
  3. Send it back to ADCO and have the AAC 51T pinned on it.
    FWIW, I do not have any other AR lowers at this point.
    Thoughts? Pros/Cons on any of the options?
2

This really sounds like a personal opinion question. Do you really want to shoot 5.56 through your 7.62 can? If so, unpin it. If you don’t really care, leave it as it is. Personally, I wouldn’t even worry about putting it on your 5.56 upper. Subsonic 300BLK is way more fun.