What can I do to Finish this?

I added a .25 cal ST barrel to my Condor, modified it for a Quad-rail and added some shinys, but I need to cap it off with something to finish it and protect the end of the barrel, but with what?

I have a shroud,but It adds 9”past the end of the quad and I dont like the extra length. The wt and balance like it is now is just perfect, so an extention no more than 3” past the barrel tip is what I would like.

There is a lot of room inside the Quad to redirect air if I seal it with a tube insert , so Is it possible to make some kind of short baffeled cap on the end without creating accuracy affecting turbulance? I dont need it whisper quiet, but just take some of the Ka- POWW 😯 out of it.

Thanks,
Tag