- Location
- Manitoulin Island
I took my MkII no star apart to glue & clamp cracks in the stock. While I was at it I decided to remove 100 years of crud and free up the fine adjustment on the rear sight. In the process of doing this, I noticed looseness between barrel and receiver. Having read how theseMkII threads were tighter than the hubs of Hell, I was intrigued. Found that when the setscrew that is pictured protruding is removed, the barrel unscrews quite easily. It is a LH Buttress thread. You can see the square thread shoulder on one side and the 45 degree shoulder on the other side. The larger setscrew shown in the bottom view is ground on an angle on the back side and straight across, looks like it was contacting the barrel sholder on the front. You can see it between the bolt lug and body in the end view of receiver. I think the bevelled side must have to do with guiding cartridge into chamber. The small setscrew tightens up against the square shoulder of the section cut out of the thread in the third picture. Perhaps this method of assembling Barrel/Receiver was only used on early MkII's. Couldn't have contributed a lot to accuracy or headspacing if the setscrew got loose.
Bill
Bill


















































