Here is something to ponder on.
Hmmm.....
Other than the bolt sleeve, it looks suspiciously like the action Emil Koshollek built. Is it?
The only picture I've seen of it is in Linden's Gunstock Finishing pamphlet on page 9. The caption says Koshollek built it "lock stock and barrel".
The cocking knob in your picture appears to be much like an '03 Springfield, while the one pictured in Linden's pamphlet is a smaller diameter. All else looks identical.
The rifle in Linden's pamphlet says chambered for ".250 caliber". Savage....Roberts.....wildcat?
