Chinese SKS: Failure to eject / sticking cases

[Pavel_J]

This is probably loading up the extractor which have been know to break.

That is the reason I only test fire once after I try the rifle out after polishing. I never have stocked repair parts and they are getting more difficult and sometimes impossible to find for many obsolete milsurp firearms.

[cootertwo]

So what do the rims look like on the stuck cartridges? Extractor ought to leave a pretty good mark or groove. Or maybe I didn't read enough. Is the rifle cycling, but leaving the case stuck in the chamber, or is it just not cycling ????

[Pavel_J]

So what do the rims look like on the stuck cartridges? Extractor ought to leave a pretty good mark or groove. Or maybe I didn't read enough. Is the rifle cycling, but leaving the case stuck in the chamber, or is it just not cycling ????

After I tap the case out of the pitted chamber the rim doesn't have any damage. The extractor releases them normally. The extractor is in excellent condition. The case gets stuck after the round is fired and cannot cycle because the pits in the chamber have grabbed it. If the pitting wasn't there and the chamber was smooth it would cycle.

This rifle is a lesson on the necessity of cleaning a firearm immediately after firing corrosive ammo. The history of the SKS is that it was bought new in the importer's box at a gun show in about 1990 (or earlier) along with some surplus ammo that the original purchaser probably had no idea was corrosive. He probably ran about 100-150 or less rounds in it and appears to have never cleaned it. After he died I was given the rifle by his family and discovered this relatively new rifle is screwed. It's so pretty on the outside it is difficult to believe it is so trashed out on the inside. I've tried to salvage it, but so far have been unsuccessful.

[ramblin84]

P_J, if one round is loaded and fired, what kind of hand pressure is required to cycle the bolt?

[Adrianople]

Also the gas tube could leak too much, or the barrel gas port could be clogged or undersized.

[branflakes]

Is the extractor strong enough to hold bcg from cycling? It has been my experience the extractor lets go or can't hold onto the round as the action is blown back from the shot. Failure to eject situation.
If it is still holding onto the rpund after being fired, most people I know would still use charging handle to extract spent round. Holding handle and hitting butt on ground or bench or use something like a mallet on the handle.
I have also seen the extractor cut a small dimple in the spent round as it cycles.
I guess my question is; is it not cycling because it still has a hold on the spent round and the stick case is what prevented the cycling? Or did something else cause the carrier group not to cycle?

[Pavel_J]

P_J, if one round is loaded and fired, what kind of hand pressure is required to cycle the bolt?

Hand pressure will not cycle the bolt because the spent case is quite stuck in the chamber by the pitting. It won't budge for me. I'm no weakling, but I'm not a gorilla either.

Also the gas tube could leak too much, or the barrel gas port could be clogged or undersized.

I have a gas port scraper tool that is made for an SKS. It came in the cleaning kit that is in the rifle butt. It goes inside the gas port easily. There is no carbon buildup in the gas port. The gas port came from the factory already drilled to the proper diameter.

Is the extractor strong enough to hold bcg from cycling? It has been my experience the extractor lets go or can't hold onto the round as the action is blown back from the shot. Failure to eject situation.
If it is still holding onto the rpund after being fired, most people I know would still use charging handle to extract spent round. Holding handle and hitting butt on ground or bench or use something like a mallet on the handle.
I have also seen the extractor cut a small dimple in the spent round as it cycles.
I guess my question is; is it not cycling because it still has a hold on the spent round and the stick case is what prevented the cycling? Or did something else cause the carrier group not to cycle?

Apparently the extractor on this rifle has been strong enough to hold the bolt from cycling. I don't beat on the bolt handle with a malet to remove the stuck case because I do not want to break the extractor. The extractor is already getting stressed too much during my test firings. Why beat on it unnecessarily when I don't have to? That is why I use a rod down the barrel into the empty case to gently tap the bolt open and free the stuck case.

I kept the casings from my test firings of this rifle just to examine the progress of my chamber polishing attempts. There are no marks from the extactor on the cases after test firings. The extractor is in excellent condition. Sometimes an extractor will scrape the lacquer on the case as it pushes onto the rear of the case and snaps onto the groove in the rear of the case. My extractor hasn't done that. Apparently it tightly grips the case during test firings and hasn't slipped off even though the case sticks in the chamber. Maybe a worn out extractor might slip off from a stuck case, but mine doesn't do that so far.

In my opinion from working with the rifle, the carrier group is not cycling because the stuck case is preventing it from cycling. Everything else on the rifle is good enough to operate the rifle. If the chamber pitting causing the stuck cases were to be miraculously polished smooth, I believe the rifle would cycle properly. The big problem is whether the chamber pits can be polished out without taking too much material from it. I don't want to be pessimistic, but the photos of the pitted chamber I posted at the beginning of the thread aren't the same as looking at the damage with the gun in your hands. I've already polished the crap out of the chamber and it is still pitted after all the work I have already done on it. The pitting is extensive.

Very soon I will try some different polishing methods on the chamber. It is very time consuming, but I have a notion to try again. That seems to be the most cost effective method to invest in an attempt to salvage this damaged rifle. If I fail it will go back in the closet as a parts gun.         

[ramblin84]

P_J,  that’s a very good summary and I now agree with what RV has said, the chamber is the culprit.  If the chamber is nominally sized correctly which seems to be the case with your cold round insertion/removal, then you’re only dealing with the friction created by case/coating expansion into the pitting.  The trouble is in trying to remove the pitting you are basically over sizing the chamber.  My view is this could lead to bigger issues at some point which become unrecoverable.  Rebarreling might be your only option.

[Pavel_J]

P_J,  that’s a very good summary and I now agree with what RV has said, the chamber is the culprit.  If the chamber is nominally sized correctly which seems to be the case with your cold round insertion/removal, then you’re only dealing with the friction created by case/coating expansion into the pitting.  The trouble is in trying to remove the pitting you are basically over sizing the chamber.  My view is this could lead to bigger issues at some point which become unrecoverable.  Rebarreling might be your only option.

I've posed a hypothetical question to a couple of friends of mine. One is 85 years old and the other is 72 years old. Both have been owning and shooting guns since they were old enough to. I asked them what they believed would happen if a chamber was a little bit oversized. Both told me the gun is screwed up anyway. What do you have to lose? The damage to the chamber is probably unrecoverable anyway and you might miraculously salvage a junk gun.

I then asked how dangerous is it to oversize the chamber diameter. One wouldn't give me a definitive answer and the other said it would cause split / broken cases, but he felt it wasn't dangerous. His opinion was the gun wouldn't blow up. I'm the guy pulling the trigger, so ultimately the decision would be up to me. I will say that every time I test fired the rifle between polishing attempts, I shot it one handed and as far away from my face as possible into the dirt backstop with safety equipment on.

I then asked if there was a cost effective way to measure how much is too much oversized diameter. I asked, would a go/nogo set for headspace do it? One guy declined to answer-above his paygrade. The other guy said headspace and chamber diameter are two different things. One is length and the other is diameter. I believe he is right. Basically that is what I've gotten out of my internet reading about headspace. I'm just a trigger puller that does some light do-it-yourself stuff, so what the heck do I know? In any event, I don't own any headspace gauges and they aren't cheap. So I really don't have a way to measure if I polish out too much diameter from the chamber.

That is why I stopped this project 4 months ago. I recently thought about revisiting it again, but I'm on the fence about wasting more time and effort on it. That is why I posted this thread. I have spent a lot of time asking other people's opinions about it, but I always hope there is something else I haven't heard before. 
 

[Filroy77]

Ideally filling in the pitting with some material would be optimal. What that material is I don’t know. Over fill and smooth out much like drywall mud. Some type of epoxy maybe?  It has to stick and not fall out, withstand high temps and the shock from being fired.

[Pavel_J]

Ideally filling in the pitting with some material would be optimal. What that material is I don’t know. Over fill and smooth out much like drywall mud. Some type of epoxy maybe?  It has to stick and not fall out, withstand high temps and the shock from being fired.

I read somewhere on the internet that someone had claimed to have screwed a threaded rod into the rear of a steel case and smeared epoxy on the exterior of the case to smear it inside a pitted chamber. After removing the case and allowing it to harden he finished it off with sanding it smooth. This person claimed he was able to get the rifle to cycle. Other people on the forum picked that apart and said it wouldn't last longterm and would eventually fail for a multitude of reasons. I don't know the outcome.

Personally I think something like that is a temporary bandaide. My opinion, of course.

I often wondered if there is a professional gunsmithing service that advertises that it can miraculously repair pitted chambers with coatings, plating or other propietary method, but the fact that I've never run across anything remotely similar to that speaks volumes. No one has reliably been able to get something like that to work to the point they would charge money for a service like that and take on the liability. I don't think something like that exists.   

[Filroy77]

The options are replace the barrel, make it a parts gun/club, add material or take away material. What’s the melting point of lead with antimony in it? Don’t know where to even begin with that. Seems like it needs braised but how to get there is another question.

 It might make fine mail box post. 

Maybe XT has some ideas, being a gunsmith and all and a man that thinks outside the box.

[ramblin84]

Continuing down this thought path, applying material is the easy part.  Even J-B Weld liquid metal would probably work.  The challenge will be reaming the chamber while maintaining concentricity, head space, etc.  I’m guessing that’s an operation that would have to be done on a precision lathe by a trained gunsmith which takes you back to square one.

As for replacement barrels, unless someone here has a spare, the ones available are all pinned, later models and wouldn’t work if you have the short or long bushing attachment.  At least that’s what I found from my quick oogle search.

[Rocketvapor]

From left field here;
Try a round of brass cased ammo.

[Pavel_J]

As for replacement barrels, unless someone here has a spare, the ones available are all pinned, later models and wouldn’t work if you have the short or long bushing attachment.  At least that’s what I found from my quick oogle search.

After my failed chamber polishing attempts 4 months ago I started leaning toward rebarreling the rifle. The expense and hassles involved chased me away from that. Even after throwing a bunch of money into something like that there is no guarantee of success.

Right now there is a long lug screwed Russian SKS barrel on Ebay that would cost me $237.00 with shipping & tax. I believe it would probably fit my pitted long lug screwed Chinese SKS. Maybe it wouldn't? The Ebay photos of this Russian barrel show that it looks good on the outside. A demilled section of the receiver is still screwed into the barrel. I even wrote the seller to get more info about it. He wrote back, "The barrel is great inside, very shinny and new looking. It is a screw on barrel." Very prominent on the listing it states: Seller does not accept returns. So I'm gonna shell out $237.00 to see if this barrel is acceptable? If it turns out to be junk I can't return it? Thanks, but no thanks!

Even if it is a good barrel I still have to pay a competent gunsmith to fit it on my receiver and get the headspace right. I don't even have a clue how much that would cost. Just pulling a wild number out of thin air I would guess $250-$300. I'm probably way off from what it would eventually cost.

I might take a chance on the Ebay Russian demilled barrel if it were a bit cheaper. I could make an offer of $100.00. With shipping and tax that would be about $129.00. Do I really want to place a $129.00 bet and possibly lose? I don't know.

That is an example of my choices if I decide to go the barrel replacement route. A lot of uncertainty.