I have what will no doubt be a silly question but after a bit of looking around here it is.
I bought a new sauer rifle and am unsure what the thread is on the muzzle. the barrel is 19mm diameter and the threaded part measures 17mm. being a sauer it will be a metric thread I know that much. but which thread is it? I first thought that it was m17 but looking at mods on the net there doesn't seem to be any so I am now wondering if its an m16? I am not sure if the size is taken from the peaks or troughs of the thread. I checked my calipers against a bullet head so know they are fine (I did wonder).
any help appreciated.