Ian the steyr trigger hole for the bar \ rail is coming up at 3.8mm ( give or take ) but it will tighten up or loosen off a bit.
I can not measure the steyr trigger bar \ rail due to the trigger guard getting in the way sorry.
My rifles are =
PCP: Steyr lg110 hft 2014, HW100 SK ( back up & rainy day rifle )
Springer's: HW77 ( 1980's version ), HW35 KLS.