The Mk. II (1905) has the large left hand modified buttress threads, locked in place by a set screw. Usually very easy to remove. The exception is the Mk. II** which has square threads like the Mk. III.
The Mk. III (1910) has right hand square threads.
Isnt it a slow twist like 3 TPI?
Now I am completely confused. This rifle is a 280 not a 303, sporting not military. Marked 1910 not 1905. Can we try again ?
I had it rebored to .308 to clean up the horrible pitting in 280. Sadly the reboring company did a horrible job, never checking after intial drill out. Thus pitting is left under the new rifling which is horrible as well.
I am awaiting their explanation.
I am thinking of doing a "stub barrel" as is done in K31 Swiss rifles where the old barrel is cut off, drilled out, threaded and new barrel installed in the"stub".
Pitting may have been too deep for the rebore to get rid of it. - dan
At some point, I had an original copy of the Ross M10 Barrel Blueprint. For those going forward, this is a reproduction, 100% copying the original print.
Ross Rifle Barrel BP, on Flickr
Ross Rifle Action Wrench BP, on Flickr
There. F'ing huge now.