Saiga feed issues

[Alabama]

Went to the range Saturday with a buddy who brought his Saiga in .223. He said it had had a jam the last time he took it out that left the bolt in hold-open position. This time he started stovepiping after about five rounds. Every piece of brass had a characteristic crease about midway except for the first round, which had always showed a dent in the mouth of the cartridge. Never wanting to miss a chance to study the AK action, I asked if I could break it down and look for a cause. I traced the crease/mark to to the bolt's bottom where it's evidently catching the next round after stripping the top round from the 10-round magazine. I showed him the brass residue on the bottom of the bolt and matched the mark and the bottom of the bolt face and he agreed.
Here's the weird part. When we put the next magazine in (he loaded 4 or five rounds each time, never filling the magazine) it failed to feed! First it looks like the magazine spring's too springy, then it won't feed at all. It happens with both the mags he brought. Dropped the mag, cleared the (empty) chamber, reinserted the mag and charged and no problem until a stovepipe on the third round.
Do these magazines just need more 'breaking in;' Can the magazine spring be so hard it wedges rounds too tightly to be stripped and chambered? The magazines are plastic with a steel follower, if I recall correctly, 10-round and, to my knowlege, original to the rifle, which was clean and well-oiled. He's put about 200 rounds through it since he got it, he told me.
I have a tendency to miss the obvious in dogged pursuit of the unlikely and overly complex, but I'm thought someone else may have seen this issue before.

Really bummed him out when the SKS out-performed the Saiga.

Any ideas?

[Onepoint]

Factory mags right? They have the Izhmash marks?
That isn't normal, I have 2 223s and the factory mags have never malfunctioned  at all.
My mags have polymer followers

I doubt the spring has so much pressure it wont let it strip, if that was the case it would probably hang the bolt when it hits the shell or half feed the shell.  Your description says its riding over which would mean the shells aren't moving up before the bolt is engaging them, just my guess anyway.  First, disassemble and clean the mags for starters and run the followers down and see it they stick in a spot. 

Sorry I am brain dead today, if you said it does it with more than one mag, then its unlikely both have went bad.

Which would sound like short stroking, where the bolt doesn't go all the way back to feed the shell and rides over the case and pushes it forward. 

First make sure its not an ejection problem by single feeding shells, if they eject and clear fine do 2 shells and see if it feeds.

Make sure the gas tube is tight and nothing funky, make sure the bolt hold open isn't being engaged somehow, like the spring broke etc, make sure the carrier return sprint retainer is all the way in the slot and not hanging up.

[Alabama]

Thanks, One.
Mag was probably polymer follower, (admitted, I was WAY too excited to strip it  ) but the gas piston was dusty/dirty, now that you mention it, and compared to the rest of the rifle was slap dirty. Could very well be a dirty/obstructed gas port causing the short stroke. It would help explain the funny dent in the cartridge rim on the first round, too (I don't see that dent gettin there with a bullet in the cartridge and firing properly. It has to happen on the ejection, right, caught on the rim of the chamber but not enough to jam? Hmmmm).
And I didn't see evidence of half-feed. When it ran it ran. No unfired stovepipes; no chamber jams. What confuses me is that it really seemed the bottom of the bolt face was catching the next cartrige; the second in the magazine; Now that I think about it the short stroke could produce the same effect. The second cartridge could catch the bolt on the way forward if it's not moving as fast as it should be 'cause it didn't go back as far as it should?
When it feeds it chambers fine, (when it feeds) so that enforces the elimination of the magazine as cause, to my mind. It did seem funny, since I've never seen a mag spring that strong! 
He called his gas tube loose, but by my standards it wasn't. There was no significant rattle and the piston fit smoothly. I'm guessing since I saw the gas piston caked with carbon he's not cleaned that area as well as he did the receiver/bore. Carrier return spring was definately all the way, no prob there.
And the short stroking could also account for the stovepipe fte's. Also, the piston was bone dry, giving me the idea he didn't give it much attention.
I'll tell him about the gas piston port and let you know if that clears it up...

Ah, my favorite pragmatist... Somehow I knew someone here would pull me down to earth.
Muchos gracias, bro.

[5thShock]

  There was a post on Gunco or AK Files about the firing pin retainer pin (or was that the extractor retainer pin?) walking out so that it was above the surface of the bolt and dragging on the carrier bolt cam raceway.  Caused enough drag to give short stroking.  This may not be the problem here but it is easy to check and easy to fix.  I think the guy used some Loct-tite when he pushed the pin back in.  Then pin should be just below the surface of the bolt.

[Alabama]

iring pin retainer pin (or was that the extractor retainer pin?) walking out so that it was above the surface of the bolt and dragging on the carrier bolt cam raceway.  Caused enough drag to give short stroking.

Interesting...
Keep 'em coming!

[Onepoint]

Heh, Its not fixed yet, the cudos are premature.

The brass will have the rims dented if its cycling right. They come out during ejection off the ejector nub on the receiver rail  spin around and hit the receiver cover and put the little dent in them.  Its the dents and scratches in the middle of the case that will be a clue to short stroking. 

The 3 you see are what they look like some dent a lot some hardly at all. Just depends on how hot the round is and where it hits.  This one with the dent in the middle is a double or misfeed from a mag that the bolt hit on the side IRRC, just for comparison.


It has to be extremely dirty to not run, but if there is carbon around the outside of the gas tube anywhere, that may be where its leaking enough gas to make it short cycle.  Though I think that a very rare in any AK, it doesn't take all that much gas to make it run. Once it starts a lot is done with the inertia of the weight of the bolt and carrier.

[Alabama]

This one with the dent in the middle is a double or misfeed from a mag that the bolt hit on the side IRRC, just for comparison.

That's the mark!

The case rim dent was evident on the first shot from the mag (and deep) but never for any shots after the first, the ones the ejection/feeding issues were happening with.
I didn't see any carbon on the outside of the gas tube indicating a leak, but I didn't white-glove it. I did see a lot of carbon on the gas piston itself, but nothing I thought was out of the ordinary.
So we'll check for a dirty gas port and/or a leaky/dirty gas tube, and insure the firing pin retaining pin isn't working its way out.
I think he'll be pleasantly surprised, since the next step he sadly planned was to be a trip to the gunsmith. Though he might still be headed that way, I think this is a promising lead.
Thanks for the pix!

[jimmy_stikx]

Has he tried different ammo?

My Cetme would short stroke and stovepipe 0ne out of 40 or 50rnds when I shot surplus though it, but new manufacture .308 so far cycles it everytime.

Maybe something to pursue, maybe not.

[Duct Tape]

I was under the assumption that Saigas dented the "brass," and that was just one of "those" things. Mine dents casings--Not a single failure to date, though, and have melted parts of the handguard (x39).

Has your friend modified the rifle--feed ramp, ect... or is it stock?

[Duct Tape]

http://forum.saiga-12.com/

[Alabama]

Thanks for the suggestions...

To my knowlege, he hasn't tried any other ammo. To tell the truth I couldn't even say what he was shooting (he works in the medical field and got called off the range just moments after we set up! Bummer!)

And he's not modifed anything either, best I could tell. The mags were hard plastic and showed some gouges at the feed lips, but I don't think he's shaved anything off there for fit. He's not inclined to modify his rifles at all, in fact, when he had this issue his reaction was to clear the rifle and set it aside until he could take it to the gunsmith. I had a hard time convincing him to put a few more rounds downrange to help show what the problem was. My hope was to save him the $$ by finding the simple solution, provided there is on.

To update here: We're still working out a point in our schedules when we can get it apart and eyeball around the gas port area, etc. One of these days...

Thanks again for the ideas. Duct Tape, I'll pass along that link; looks like a lot of information there.

[Lollygagger]

One...

Be sure you have a correct Saiga mag -it is synthetic with a synthetic follower.

And, that the molded in PROJECTION at the top front of the mag is there...has not broken off. This is what bumps the round up to feed, since a stock Saiga has NO BULLET GUIDE in it to ramp up the round.

And, yes -they are stiff. The ruskies use a spring appropriate to a 30 round mag (no kiddin'). However, it works.

Lastly, yes...ammoo types can be problematic in use with these -try ball, avoid SP & HP when possible.

Report back. Good luck.

Lollygagger  (cases get bshed pretty good in just normal use)

[Alabama]

Report back.

 
I'm eager to see whether we can clear this up myself. Soon as I can get this father of two small children to sit down a minute I'm betting we can.
Great point on the projection, Lg -- the mags were synthetic, I'll check to make sure they were orig.

[Lollygagger]

The factory Saiga mags (10 round) in 7.62x39mm & .223 look about the same externally.

Like so:



Yours should appear like that. Does it?

Lolygagger