My Caspian slide arrived which allowed me to start fitting the barrel, or at least the barrel hood. Fitting the top barrel lugs and cutting the bottom barrel lugs will have to wait for the frame.
In what I expect to be the typical fashion for this build, I measured a lot before I ever got out my files. And I rewatched this Mosin Virus video which has been the most helpful reference for this work that I have found.
The most important tool for me at this point, besides files, is the Barrel Alignment Block from Brownells (seen near the top right of the adjoining photo). It is used to ensure that the barrel hood is fit while the bottom lugs are exactly vertical in reference to the slide rails.
Following Mosin Virus’ method, I measured all the distances to get ready to start filing the outside edge of the hood. But I could not figure out a way to get a repeatable measurement for the distance from the outside edge of the barrel hood to the outside of the slide. Without that, I began by taking that edge down. After a little filing, I blued both hood edges, attempted to fit the hood into the slide notch, and noted where I needed to file more.
Taking my time, filing just a little, and rechecking with blueing, I got closer and closer to a fit until the hood slipped into the notch with just a little resistance. I left the slight resistance because I knew I’d need to add a little clearance later, but wanted to wait to do that once the hood was filed to length. I wish my filing technique was better because the hood edges are not perfectly straight, but I think they will do.
Getting the hood length right was confusing and took me a lot of time. I reached a point that I thought the hood was short enough to not contact the breech face, but the upper lugs would still not start to engage. Maybe something else was holding the barrel out?
After putting it down and starting again the next day, I could see that there were very narrow marks in the blueing showing me that there was contact. More light filing, blueing, and fitting finally got me to the point that the barrel engaged with a satisfying click, but still came out of engagement without resistance.
Not having the frame yet, I could do any more barrel fitting now. But with both the slide and barrel on hand I could take the measurements necessary to order an EGW Thick Flange Bushing along with several other EGW parts I’ll be needing later.