WTK: Muzzele Thread Size for my Swiss SG 510 T AMT

My Swiss SG 510 T AMT (American Match Target) was imported without a Brake/FH. Does
anyone have any idea what pitch and size the threads maybe on this barrel? I was planning to go to HD and buy some nuts in several different metric sizes and see what one threads onto the barrel.

https://www.milsurps.com/images/impo...0/QnE21P-1.jpg
https://www.milsurps.com/images/impo...0/fDbdcA-1.jpg

I got my answer from Kontaktaufnahme in Switzerland.

"The muzzle thread should be an M15x1. The muzzle brake of the FN-49 should work and you see that sometimes on these rifles."

I seem to recall that as the same thread on a G3, as well