I just shipped a barrel to Pete Athens to remove the tulip FH and check nut and install an AAC 51t FH.  I meant to send my 1/7 twist barrel for the FH swap, but I am now second guessing whether or not I inadvertently shipped my 1/9 barrel instead.  Steyr’s barrel markings when it comes to twist leave a lot to be desired.  The barrel I’m looking at on my workbench right now is devoid of anything that resembles twist rate identification.  Is there an easy way to tell the 1/7 and 1/9 barrels apart?

I believe that mine has a number 7 on it. I will check in a bit. Not sure if they were all marked in such a way.

Yes mine has a number 7 stamped on the barrel. I had intended to post a photo but that doesn't seem to work the way I am used to on this site. The 7 is stamped more lightly than the caliber designation, etc. but is in line with it.

There were two runs of 1/7 twist barrels made by FN. The first was back in 2013. The second was more recently, like less than a year ago.

The first run was stamped with a "7".
The second run was not stamped , but FN sent them to steyr with hang tags denoting twist rate. Those hang tags were taken off before packaging to ship to customers...

Pull a patch/rod through what you have and count revolutions to know for sure.