Unreliable SKS

F

fmjgordo

Inactive
I took my sks to the range today. Every so often it would not fire. I could go 30 or 40 rounds everything functioning as should. Then it would let me down. I picked up the unshot rounds and they looked like the firing pin wasn't hitting them hard enough. The rounds my gun didnt shoot shot fine out of my buddies chineese sks. Does anyone make firing pins other than the floating style for a yugo sks? Any help would be appreciated.

-Gordo-
 
sks

Dear Shooter:
Never heard of an SKS Siminov being unreliable; it sounds like you've got excess headspace - have it checked!
harry B.
 
Possible hammer spring problem...you should have taken your SKS apart and compared hammer spring tension of your gun vs. his Chinese SKS.

Check to see if the firing pin is damaged or broken. It's possible it may be broken and not long enough.

Headspace may be in excess (like the above post suggested).
 
I think the problem is fixed. I didn't think the firing pin would be as dirty as it was. I couldn't even move it back and forth. To get it out i had to lightly tap it with a hammer and punch. I cleaned it with some degreaser and oiled everything good then put it back together. The gun only had about 300 rounds since the last time I cleaned everything. I guess i'll start completely disassembling the gun and cleaning everything after every outing. Hopefully it lives up to its name next time. Thanks alot.

-Gordo-
 


You should only need to take down the bolt every 1000 rounds or so. When you grease it, wipe most of it off. You need a thin layer, not a glob that traps dirt and unburnt power.



-tINY

 
I learned the hard way(or fun way, depending on how you look at it) via a slam fire at the indoor range a week ago, that excessive oil on the firing pin is a good way to attract all kinds of gunk in the bolt. Now, I just give it a spray with Berryman's B12, and the red straw fits in the bolt hole perfectly.
 
Glad I read this before i put the bolt back in the gun. Come to think of it I probably left to much oil on it last time I cleaned it. It makes sense now that I actually think about it. All the excess oil is good for is making stuff stick to it. I'm the only one in my house who has any firearms so I have no one else to go to for tips.

-Gordo-
 
The oil issue is a problem. You might want to consider using a semi-permanent lube like Moly Fusion oil. It is applied by swabbing to warmed parts inside and out for about 20 minutes, and results in a corrosion resistant molybdenum compound of iron phosphate and molybdenum forming on the surface. Think of it a Parkerizing, but with a 50 millionth's thick teflon-like coating resulting rather than a thick phosphate surface. It helps keep carbon and other residue from sticking to the surface.

There are some other semi-permanent lubes. Sprinco's Plate+ Silver uses a colloidal suspension of acid-neutralized sub-micron molydenum disulphide in a petroleum-based carrier that bonds to metal and gets into surface imperfections to provide a sacrifical surface. Because the carrier and lube are petroleum and molybdenum disulphide-based, it won't be as temperature immune as the MolyFusion and it doesn't work on non-ferrous metals as MolyFusion does.

The variouis Teflon burnish-in treatements, like Mill-comm's are another thing that will leave a dry surface that should resist dirt build-up. My guess is the MolyFusion will be the most satisfactory for the bolt, though, because of the hard corrosion resistant and carbon-shedding layer it forms. And I believe you can add either of the other products over top of it if you want to try?

Nick
 
Tiny,

I think you'll find the Tetra fluoropolymer is closest to the Mil-comm products. It is not much like either the MolyFusion or the Sprinco Plate +, however. Both of these products work as bore lubricants, and the MolyFusion, in particular, resists temperature well up above the melting points for fluoropolymer or even for molybdenum disulphide, if I am remembering correctly?

Back in the late 80's when Teflon (DuPont name-brand fluoropolymer) was all the rage in new gun lubes, there was a product that Smith & Wesson eventually distributed called Friction Block. It was being burnished into barrels and got velocity increases (50-100 fps in highpower rifles) and cleaning improvement results similar to the other two products in a bore, but the benchrest community soon found it actually deteriorated accuracy. Apparently the properties of the Teflon fluoropolymer tend to change too much with temperature for consistent bore behaviour as a gun heats up. I don't know about Tetra's fluoropolymer, but it comes from that same era?

On the other hand, I believe Microlon Gun Juice, another bore treatment, is also a fluoropolymer-based lube and it apparently does well, at least in small bore and hunting-accuracy rifles. I don't know whether the benchresters have messed with it? It is probably the oldest barrel lube treatment product.

Microlon Gun Juice (in smallbore) and MolyFusion are the only two products for which I've seen testimonial claims of significantly increased accuracy. Whether this is due to the lubricant or simply because it alters barrel time for the bullet to a more favorable number for the particular load being tested, I don't know? If the latter is true, adjusting the load would get the same result. Friction reduction should, theoretically, reduce barrel heating and any POI shift associated with that. This might be the another mechanism it has for improving groups?

So many experiments to try; so little range time.

Nick
 


For the firing pin on an SKS, I think anything that leaves a barrier to corrosion and doesn't trap residue is probably fine.

I can't imagine any of them affect the accuracy enough to tell in anything other than bench rested shooting with heavy barrels and those wierd people behind the trigger (I have a friend that does this - no slight, only observation).



-tINY

 
Tiny,

I'm sure you're right about the bolt. I only mentioned accuracy effects on bores lubricated with the different products as an illustration that their properties weren't really the same. That said, Shooter's Solutions posts testimonials from people cutting group size in guns. These are 1-1.5 MOA shooters coming down to 3/4-1 MOA; not benchrest accuracy guns. The thing I don't know is the mechanism of the accuracy improvement for this or any other barrel lube? Like firelapping, a substantial improvement in ease of cleaning is guranteed, but improved accuracy is not.

Nick
 
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I have a similar problem w/ my Yugo SKS. I am at the point where I am going to try to buy a spring-loaded firing pin from these guys:

http://www.murraysguns.com/sksown.htm

I haven't yet contacted them to see if they are in business but if they are, I'll be placing an order soon.

At the present, I can't get my firing pin out of the bolt. The pin that retains the firing pin is out along w/ the extractor (no problems there)... firing pin will only come out of the bolt about 3/8". I have used a steel punch to try to gently tap it out w/ no luck. Last time or two at the range it has had more than one double-fire per mag so its not worth having it go full-auto via slam fire. Each time it would double fire, I would pull the bolt and find that the firing pin was sticking out ever-so-slightly and pretty stiff to try to get to go back into the bolt. Not worth huring myself or someone else at the range so new bolt/firing pin will be my last resort. I have almost 800 rounds so I need to fix it up to use all of that ammo... :D

One time the pin was stiff was undoubtedly bacause I tried to use Rem-Oil on the pin. Powder + Rem-Oil = sludge. This last time I disassembled everything, used a small dremel attachment to brush off all residue, then cleaned and thoroughly dried (looked brand new!), reassembled... same problem after about 100 rounds.

I could be doing something else wrong or overlooking something but the bolt & firing pin problem boils down to a safety issue so I'd rather be safe than sorry.
 
A lot of the military type rifles were stored in Cosmolene. There may still be some in the firing pin channel which will turn to a very strong glue when mixed with powder residues. Solvents alone may not work on it. A tiny "bore" brush that fits perfect can sometimes be found at electronics supply stores.

Check the firing pin itself for burrs in the notches. A small file will clean them up fine. This is actually quite common...I find them that way all of the time. Removing the burrs and ragged edges does wonders for freeing up the firing pin in the channel.

Most important!!!~~...I'm not sure about the Yugo's but the "others" all have a firing pin that can fit just fine up side up or up side down. Up side down will result in a runaway slam fire due to the firing pin being locked in the full forward position. Check that it's free in the channel after you install it!!~

Keep yer powder dry, Mac.
Mac's Shootin' Irons
Tuff-Gun Finishes. The Name Says It All
http://www.shootiniron.com
 


Hadn't thought about cosmoline...

Soaking in mineral spirits or MEK overnight and then blowing it out with an air compressor would be a good approach.




-tINY

 
Actually, Ed's Red, having two polar and two non-polar solvents does a good job on about any hydrocarbon-based material, not just powder residue. The fact it gets both likely makes it ideal for chasing down traces of powder/cosmoline mix.

Nick
 
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