I bought one of the UK-59 barrels from Classicarms. My friend bought one also. This is about my build.
I started out with a hex m91/30 that I also purchased from Classicarms. It was a "hand pick" and that means nothing to them. The stock had several repairs and was in overall bad shape. I took it out and shot it a few times and even though it was a reasonably good shooter I have another that was better so this became the donor gun.
The UK-59 barrels listed on classicarms were also conveniently photographed from all the best possible angles. IMO, this was done intentionally but thats another story. The barrels are not a screw it on and go as I have read many different places. While I am not a gunsmith I do have a clue. I will do my best to explain what was done and why.
In the first pictures I will show what the original barrel looked like.
Picture #1 is the UK-59 barrel as purchased. Note the slots and steps in the barrel.
Picture #2 shows the end of the barrel that screws into the Mosin receiver. Note where the threads end and it steps up to the machined surface RED ARROW. The "step" is where it mates with the Mosin receiver. The way these barrels are machined leaves very little mating surface and it will not hold up in the long run. I will revisit this in a later post.
Picture #3 shows the same end as picture 2 from a different angle.
Picture #4 Shows the business end. It was very poorly machined.
Last edited by springer-; 02-26-2012 at 08:29 AM.
We machined the barrel down to remove all the slots, steps and stamped in numbers. Then we machined a press fit sleeve to increase mating surface of the barrel to the receiver. This also significantly increases the clamp load.
Picture #1 shows the increased mating surface. The RED ARROW points to the original diameter of the barrel when purchased. The GREEN ARROW points to the new diameter with the sleeve installed.
Picture #2 RED ARROW points to the seam where the sleeve and the barrel meet up. The RED LINE shows the part that is the sleeve.
Picture #3 shows the a barrel attached to a receiver with the sleeve in place. I can't believe anyone would just screw on the original barrel and expect it to last.
Picture #4 are the 2 barrels we machined next to the receivers. The Hex on the bottom is mine and the Round on top is my friends. You can just make out the seam on his. On mine it is virtually gone. More pics of that later.
I don't have a good picture of the extractor relief. The way the barrels come is very crude at the extractor relief. I couldn't close my bolt as the extractor was hitting. After a few minutes with a round file it worked fine.
I cut strips of 220 sand paper and sanded all the machine marks out of the barrel. I also sanded the receiver completely and did machined several areas.
Picture #1 is the barrels after machining and sanding.
Picture #2 shows the same with one screwed into a receiver.
Picture #3 RED ARROW #1 shows an area I machined for the bolt handle. The stock I am using it a Finn M28-66 Walnut stock. I am going to replicate much of the original design of the M28-66 including the bolt handle. This relief lines up with one in the stock . RED ARROW #2 points to where the top of the receiver was machined to allow clearance for the bolt handle.
I tried to capture the barrel sleeve after bluing. The picture was a little out of focus but it is nearly impossible to tell there is a sleeve on it.
I used a Timney trigger with a safety. I didn't like the way the safety stuck out from the receiver so I re-profiled the safety lever. I will warn against this as the lever is a hardened steel and does not want to bend without braking. It took a while but I am very happy with the result.
Picture #1 is the out of focus showing the sleeve finish.
Picture #2 shows the safety. It sits tight to the receiver and allowed for very minimal removal of wood for full operation.
Picture #3 is a before and after. We recrowned the barrels.
EDIT.... I added a forth picture that is more in focus. Also note how well the barrel sleeve meets up with the Hex receiver. Image if that sleeve was not there how far off they would be. If you compare that to a stock Hex Mosin you would find this much closer to the original.
The original M28-66 also had a heavy barrel. The stock had plenty of clearance for the larger diameter barrel. In fact I did not have to make modifications to fit the new barrel. The barrel is full floating.
In the following pictures it shows the clearance around the barrel
I've always felt the "heavy barrel conversion" using the UK-59 has been overhyped ad-nauseum.
For some with a lathe and the necessary gunsmithing skills, it could be an interesting project with a cheap barrel, on a cheap rifle.
As soon as you have to pay a gunsmith for all the work that needs to be done (and there is a lot), you'd be better served to have just bought a MATCH-GRADE barrel blank, have it threaded and chambered by the smith for the caliber of your choice (and I'd do it in .308).
As you already noted, it's a freaking machine gun barrel...just because it weighs ten pounds there's this misnomer that it's going to be highly accurate. Ummm...nope... the picture of the crown says it all.
I'm a little curious as to why you found it necessary to machine a notch in the receiver.
Very nice job on it overall. But, I gotta add my $.02 and say I think you're making a bad move with that clamp-on scope mount.
Put a Rock Solid, or adapt another d&t mount. I seriously doubt that mount will hold zero, and it won't set the scope far enough back for proper eye relief and the rings sit so high you'll need add something really tall to get a proper cheekweld.
I've always felt the "heavy barrel conversion" using the UK-59 has been overhyped ad-nauseum....
It is a cheap barrel and a cheap gun and a somewhat cheap project but it does start to add up fast. If it were not for the fact that we do all our own work it would not be a good choice in barrels.
I agree 100% about buying a match grade barrel instead of the UK-59. I am not sure why people want it so bad. We bought them because they were cheap and would be a fun project. We also hope the end result will be an accurate rifle, this remains to be seen. For $75 for the barrel it is fun but I just saw one sell on GB for over $300!!! That is ridiculous. There was also another one on GB that had been turned down the entire length to the diameter of the original mating surface I pointed out early in this thread. There would be no way to add a sleeve to that barrel and there is no way it will hold up. That barrel is virtually useless and yet it had a buy-it-now of $400 on it.
Actually I don't think I noted it was a machine gun barrel however it is. The rifling and barrel look great. After slugging it and cleaning up the crown, I think it will be a good shooting barrel but again that remains to be seen.
I notched the receiver to match what the Finn's did with the M28-76. It makes clearance for the way the bolt handle is mounted. The bolt handle should be all welded up next week and I will post pictures to show why the receiver was machined the way it was. In the mean time here is a picture of the M28-76. Note the bolt handle and how it goes straight down from the bolt.
I really don't like the looks of the Rock Solid mount. The plan is to mount a rail on top of the Hex to hold the quick release mount shown. My friend is going with the Rock Solid mount. The plan is to use his mount to locate the mounting holes in the Hex. This way if the mount I want to use doe not work out, I can use the Rock Solid mount very easily. The scope mount position is about the same with either mount so I don't think the eye relief will be an issue.
for the work involved in making these barrels right, i think i'd have just got a barrel blank from green mountain and started with that.
yo guys obviously had a lathe that could deal with it.
Hind sight is 20-20. Knowing what I know now, I would suggest anyone looking to do this conversion to do exactly what you mention. It would be much simpler, less expensive in the long run, better quality and probably more accurate.
Yeah, I do agree with you on the looks of the Rock Solid mount.
It is effective, but too bulky looking for my taste as well, which is why I used a Weaver side mount.
Forgot to mention I was really shocked by the lack of "shoulder" on the barrel you noted...at first I thought you just cut the threaded section off the barrel and cut new threads and extractor groove below the thicker part of the barrel so that you could get a wider shoulder. But you say you didn't do that...I can't visualize how you got the shoulder heavier, when there wasn't the metal there to do it in the first place? What am I missing?
And, thanks for the idea of the receiver groove, and milling down that side of the receiver- I haven't seen that done before. It will definitely help with the bolt clearance on my next one.
I just reviewed my last post, and it kinda came off rude, that was not my intent.
the work you guys did looks to be top notch, and i like what you did.
i've never been a fan of those UK-59 barrels. and a lot of people have reported the same problems you had.
here's something that would work as well 7.62 X 51 NATO Chambered Minigun Barrel Blank
and this one might have been too short, but it's got a .310 bore 7.62x39 AK Raw Barrel Blank 1.06" x 20"
.....There was also another one on GB that had been turned down the entire length to the diameter of the original mating surface I pointed out early in this thread. There would be no way to add a sleeve to that barrel and there is no way it will hold up. That barrel is virtually useless and yet it had a buy-it-now of $400 on it......
I found the pictures of the barrel I spoke of above. Look at the shoulder or lack there of. I guess it could be fixed if the barrel was threaded further up and then something threaded on that creates a new larger shoulder.
Look at the 2nd picture in the 1st post. I made a press fit sleeve that went from the RED arrow to the shoulder where the bluing start. Once pressed on, the barrel was machined to what you see.
Then look at the 2nd picture in the 2nd post and it shows the sleeve location.
Ahhh... OK, got it...
So, you headspaced the barrel using the sleeve width, great idea!...curious about the fit- did you need to chase the threads further, or did it mate up correctly like they advertise?
I have to wonder...since TGI threaded and re-profiled the barrels to begin with why they didn't go a step further and do it "right"...