take the barrel to an engineer and ask him to measure it, and yes most unmarked barrels are .688/.689OK well i was asked "what bore size is your barrel" today, and couldn't answer.
I'm aware what is meant by bore size, however i don't what my barrel is. i don't know what brand or model my barrel is and as such cant find out that way, is there any other method for telling?
thanks
Nick
A Vernier "Calliper" can be used to measure ID, OD and also depth, to certain extents.nope
nor do i know what one is
I'm assuming its a bore measuring tool, but thats just a guess