Milsurp Rescue: Sino-Slavian SKS Project

[mancat 2,368]

OK. I guess there are probably enough SKS owners here to make a thread on this, since I've been lightly covering it on another forum for SKSes.

 

This Yugo M59/66 SKS was the first rifle I ever bought for myself, for $99 in 2004. I was 20 years old, and knew nothing about guns, other than that I liked to play Counter-Strike, and guns were cool.

 

I promptly ruined it by cutting off all of the unique Yugo features with a Dremel, and Tapcoed the shit out of it, trying to turn it into some horrid AK wannabe/sniper-rifle thing. Fortunately I kept most of the original parts, so as I got into collecting and appreciating real milsurp, the stock parts that I had not destroyed went back on, and I dumped all of the Tapco garbage.

 

The rifle as it was in 2009, after fixing gas system and shortening barrel to 16" in an attempt to eliminate the lack of rifling in the remaining section of the sewer-pipe barrel. Better, but still crap:

 

 

Problem was, the barrel was fucked, a total sewer-pipe. The gas system also had horrific blowby and had to be redone, which was achieved with a stainless shut-off valve, and reamed the gas block to fit it. It cycled reliably, but couldn't stay on paper past 100 yards.

 

 

A couple years back, Numrich's showed up with stripped Chinese barrels on receiver stubs for $15/ea, so I bought a few of them just in case. Although a couple had rings, one was perfect, and despite looking like crap on the outside, it had crisp rifling & well-defined grooves, and a mirror-bright chrome lining. The barrel looked never-fired or lightly-used, and cleaned up on the outside just fine with steel wool and oil. Not having a place to really work, I set the project aside until I had my own garage to work in - now I do.

 

So, after verifying that the Chinese barrel mic'ed out the same as the Yugo barrel, and was theoretically compatible, I decided to attone for my sins and attempt to finally bring the old Yugo back to life. It will be an M59 clone, but will retain the gas shutoff valve, so that I can operate it either as a semi-auto, or a straight-pull bolt action.

 

I just decided to finally tear into the old beast last week.

 

Yugo receiver and stripped barrel - parts were very tight and had to be soaked in PB Blaster for a week. They came off reasonably well with a large brass punch and 3-lb shop hammer:

 

 

The Yugo barrel's lug snapped free easily with a 22MM wrench and 4-ft cheater bar, and was threaded out by hand:

 

 

For the Yugo barrel, PB Blaster actually did get in there and get to work:

 

 

Removing the good Chinese barrel from the receiver stub was a bitch of a chore. I ran a practice round on the shittiest barrel that had multiple rings, and it was so tight in the receiver stub, that even with a quality 22MM wrench, the barrel lugs simply deformed, and the barrel didn't move at all. Instead of ruining the lug on the barrel I wanted to use, I decided instead to relieve the threaded collar on the receiver stub, and crack the collar open with a punch. This allowed the barrel to be threaded out by hand. The barrel threads were unharmed:

 

 

The Chinese barrel indexed loosely in the Yugo receiver, about 240 degrees off from where it needed to be. This mean that material needed to be removed from the threaded collar of the receiver. Since I'm too cheap to afford a lathe, I made a rough estimate of the amount of material to be removed by measuring the distance gained between the barrel lug face and collar face by threading the barrel out 180deg. I then marked the measured gap on the collar, and worked it off with a small grinding wheel. The collar was then leveled off with a file, and the surface was slowly filed as needed to allow the collar to come to hand tightness about 30 degrees from proper index.

 

Once the barrel was at 30-deg at hand tightness, I tightened the barrel down to proper index using the 22MM wrench and cheater bar. The barrel indexed properly against the Yugo receiver rails. The ejector clearance cut lined up perfectly. Surprisingly, the Chinese and Yugo indexing marks even lined up. The barrel was staked on both sides with a prick punch.

 

The Yugo bolt came very close to dropping in, but didn't, so it will need to be adjusted and checked for headspacing..

 

 

The Yugo components were checked against the Chinese barrel with calipers before installing. Some of the components had to be polished internally to get proper interference fit. This was done simply by wrapping my finger in 1200 grit sandpaper, and running it around in circles inside the component collars, while checking the fit of the barrel journals and component collars frequently with digital caliper to get around .005" average fit. I also chamfered the pin channel edges on the Chinese barrel, as they were all slightly mushroomed.

 

All components installed easily with a dead-blow hammer and light anti-seize. The Yugo gas block was aligned and installed with the gas tube in place, to ensure proper fit, since the Chinese and Yugo gas systems are a very slight difference in length. The gas port lined up about 95%, and I don't think it will have to be reamed.

 

 

The remaining work is to fit the FSB, drill & pin components, and headspace the bolt.

 

My 2-month old son Sammy agrees: Saving old busted-up rifles is fun!

 

Edited March 14, 2014 by mancat

[akastormi 617]

As a fan of SKS's I like this. At least it was a 59/66 you cut up and not a M59. If you need something parts wise, drop me a PM.

[mancat 2,368]

I could use a standard blade bayonet. The Yugo bayonet won't work properly with a standard FSB.

[mancat 2,368]

Still not headspaced, and left FSB unpinned until I have a chance to zero it.

 

Not to upset the purists, but not being able to find any 2.5mm drill bits locally, and not wanting to mess with reaming the pin channels from 3/32 to 2.5mm, I just used 3/32 roll pins on the barrel components.

 

I also need the correct blade bayonet with the ring-style muzzle anchor. Yugo bayo installed just for looks ATM.

 

[akastormi 617]

PM sent

[mancat 2,368]

I did shoot it today, after finishing the headspacing a few nights ago. I don't have 7.62x39 headspace gauges, so I just made my own no-go and go gauges by using the tape trick to determine where the bolt stopped entering lockup on my low round-count Norinco DP SKS. Filed the Yugo bolt locking face until it matched the Norinco's lockup behavior with the two makeshift gauges.

 

Just to play it safe, I strapped the rifle into a lead sled and strung up the trigger so I could stand behind the truck door. For the first few single shots, then checked the cases and bolt locking face, then ran the remaining 20rds through it before deciding it seemed safe to shoulder up and fire it.

 

It fired 60 rounds without issue, except for one stovepipe where the spent case got stuck between the left rail and the fresh case, which was halfway into the chamber. It looks like the extractor dropped the case, so I think it will get a new extractor spring.

 

Cases looked fine. No ring or marking on the rim face. Primers came up flush with the rim face. No splitting or bulging of the case necks.

Ammo was Wolf HP 124gr and Red Army (Ukraine) 123gr FMJ.

 

I think this rifle probably had a very high round count. It was definitely used in the Balkans. I am happy to give it a more peaceful life at this point.

 

Safety first!

 

Edited March 21, 2014 by mancat

[mancat 2,368]

Well I had to pull out all the roll pins and drive the original 2.5mm solid pins in. The roll pins weren't sold enough in some of the original Chinese pin channels and would allow the FSB to roll around a little. Oh well, lesson learned.

 

Also a big thanks to akastormi for mailing me a Yugo M59 bayonet collar, free of charge! It fit the Chinese FSB without issue and allows the bayonet to be extended securely.

[akastormi 617]

Always willing to help.

[mancat 2,368]

Rifle complete & blued

 

[akastormi 617]

I like it, it came out nice.

The gas shutoff is about useless for anything now.

I'd roll the gas valve over and weld it in place through the pin hole. Thus getting rid of thumb button and smoothing out the gas block.

Just my two cents thrown in.

[mancat 2,368]

The reason I left the Yugo valve on is to see what the full accuracy potential of the rifle is when operating in straight-pull/shutoff mode. With the gas shut off, the rifle operates exactly like a straight-pull bolt action, and it's sort of fun. It increases the felt recoil quite a bit, surprisingly.

 

No need to weld it. It can be more permanently set to a position by threading it and installing a socket head cap screw. I also made sure that the gas system is tight once the rifle is assembled, so it takes some effort to rotate the valve to the desired position - it won't happen by accident. There is no valve blowby, as I already have an oversize stainless Murray's valve fitted to the block, which replaced the original plain steel Yugo valve.

 

I do have a standard gas block, so at any point I could still convert it to be a full M59 clone.

 

I shot another 120rd or so today, got zeroed in, and was shooting good at 75yd. I'll have to take it to the range though - I was just shooting offland leaning against the truck, and stapled the target to a particle board door out at my usual shooting spot, and the hits would just spray particle board back through the paper, so it made it hard to see what the groups really were, but left a primary hole about the size of a tennis ball in the center of the target. Very scientific, I know.

Edited April 13, 2014 by mancat