Update, 4/25. I put a barrel liner in the 1904, a 1-16 twist barrel. I had a .22 LR reamer, and that's what I made it. I purchased the liner and drill from Brownell's. They were running a special, so I got a slight discount. Still ran about $125. The barrel rifling was gone, probably due to corrosive ammo, and never being cleaned by it's previous owner(s). I used a cordless drill to ream the barrel. The drill is 5/16", same as the O.D. of the liner, and has a long pilot. Due to the drill length, it had to be drilled from both ends of the barrel. Neatness of the drilling is not critical. The epoxy covers up all. As long as the liner slides in with light resistance, you are good.
The liner is marked on which end to cut the chamber. I think it has something to do with which direction the rifling is cut from. I found it was easier to cut the chamber before installation. I coated the liner with Acraglas Gel, and twisting it during installation, to spread the Acraglas. I put a round in the liner's chamber, and with the bolt in the receiver, I had the liner slide up snugly against the bolt. This guarantees headspace is perfect. Just make sure no Acraglas comes out, or is left in the receiver.
The Acraglas set up in a few hours, and I let it sit overnight. I hack sawed the excess liner off at the muzzle, filed it smooth, and cleaned up the muzzle with lapping compound on a brass screw. At the chamber, a few strokes with a needle file, cut the extractor groove. The design of this rifle lends itself to very easy relining.
The rifle was acquired with a home made rear sight. I found a period correct sight on ebay, and installed it. The rifle now shoots great. Better than I can possibly hold it. The rounds chamber and extract easily. Before, I had to pry out the empties with a pocket knife. I used some Remington 22 LR, SV ammo, for initial testing and use. Someday, after I am gone, some kid somewhere, is going to get a neat little rifle.
Please excuse the winded dissertation, as 90% here already know how to do this. This is dedicated to the 10% who don't know how, and might be interested.