Just FYI, when I initially contacted Dennis Olsen to do the work, he absolutely refused to do the feeding modifications. No explanation. Perhaps he was too busy? Or uncomfortable making a standard action Mauser work with 404J? He agreed to thread, ream, and mount the barrel. That's it. Lija made the barrel and took it over to him. I brought the rifle down as a 30-06 to get around gun parts import/export regs. I planned to stay in Montana for a while so I brought tools with me to finish the job. Unexpectedly he did fit the new barrel into the stock (#5 404 profile barrel was much thicker than 30-06). Saved me some work there. And because I had the sights along he offered to install them. I had brought the taps along to do it (previously acquired them to install same model sights on my 30-06 Springfield). Left them with him and he charged sixty bucks to install the sights which was fair. THEN, he surprised me by offering to do the feeding rails and ramp. But that would have meant staying in Montana longer, probably a lot longer, than planned. Temps were hovering around 100 degrees, I had the dogs in a vehicle and trailer with no AC, and my Jimmy was acting up (vapor locking?) so I had to decline. Needed to get home.
I plan to be in the Flathead again this summer and can look at OP's gun if he wishes but I don't think it will be necessary. Perhaps someone close to him can load up three dummy rounds to test the cycling. That will tell the tale quickly. If the cartridges jump the rails too early, then he's got a big problem. If they jam during feeding (which I think unlikely), then he can breathe a sigh of relief. Fixable. Hopefully it cycles okay.
Duane Weibe's booklet describes a very different shape for modifying the rails. Mind you, I didn't follow his prescription entirely but he was building 375 not 404 and the cartridges are very different shape. OP's rails do not compare to either mine or Wiebe's illustration.
