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IZH 35M, Firing PIN too loose?

Posted: Fri Apr 07, 2006 9:59 pm
by 22dude
I have read everything available about the doubling and full auto burst with the Russian Clanker. Mine does not have burrs on the the bolt or chamber face and it is clean. I looked very closely with magnifing glasses. It seems that the force of the bolt returning is slinging the firing pin into the primer. I noticed very faint impressions from the firing pin on the cartridge case even with chambering a round. I pulled the bullet out a cartridge, poured out the powder, release the bolt on it a couple of times and poof. It fired. Scary.

I'm trying a thicker oil in that area to see if that slows the firing on cycling. Have not got to fire it yet. Will test in a very controlled, safe area.

Any suggestions?

IZH 35 firing pin

Posted: Fri Apr 07, 2006 11:57 pm
by Mike T.
I don't believe the firing pin can be too loose. Perhaps the problem is that the pin is not loose enough. If you remove the slide from the gun and shake the slide back and forth longitudinally (that is, parallel to the bore axis) rapidly, you should distinctly hear the firing pin clicking back and forth in unison with your shaking. If you don't hear it, then you need to free up the firing pin (clean the firing pin and its channel and check for burrs that might inhibit the free movement of the pin).
Check that the firing pin retracts at least flush with the face of the recess in the slide. If it protrudes (that is, doesn't fully retract), that could cause a cartridge to fire when chambered.
There have been incidences reported that the depth of the recess in the slide in some guns is not deep enough to clear the rim of the cartridge. Some brands of ammunition have a thicker rim than others and can give a "slam fire" when chambered in such a gun. (The rim is pinched all around by the face of the recess, thus acting just like a firing pin). This latter effect is not related to the firing pin itself. Measure the depth of the recess in the slide and compare it to the thickness of the rim of the ammo you are using. Apparently, EAA has reworked guns returned to them to correct such a "shallow" recess.
If you are aware of all the foregoing, and still have the problem, I must defer to others for suggestions.
Mike T.

Posted: Sat Apr 08, 2006 12:18 am
by Guest
I would be surprised if you are getting true slamfires. I suspect that the hammer is dropping with the slide. I would check the sear engagement as these pistols do not like to have that set too fine. I agree with the previous post in that the firing pin should clang backwards and forwards when you shake the slide. Try adjusting to have more sear engagement, this will prove whether I'm right or wrong!

post subject

Posted: Sat Apr 08, 2006 11:52 am
by Mike T.
Further on guest's message regarding the hammer dropping with the slide:
You can of course, with the IZH 35, observe whether the hammer has dropped, since it is visible in the opening in the top of the slide.
If the hammer is following the slide forward and if increasing the sear engagement does not rectify the problem, there is another thing to look for.
I began to have the problem of the hammer dropping (following the slide forward) after my pistol had been operating correctly for many months. The pistol even went "full auto" in one instance. The cause was a failed disconnector. When the slide moves backward, it is supposed to push the trigger bar out of engagement with the sear - otherwise the sear can not reset (that is, engage with the hammer to hold it back). Actually, there is an intermediate, or secondary, sear that lies between the hammer and the primary sear (the one contacted by the trigger bar) but that is not material to the problem. The rearward moving slide pushes on a raised hump, or shoe, attached to the trigger bar, thus forcing the trigger bar out of engagement with the pin on the sear. In my gun, this hump, or shoe, had broken or fallen off. Consequently, the slide no longer disconnected the trigger bar from the sear. Since the trigger is still being held back (after firing a shot) when the slide recoils, the sear remains pushed back and so can not move forward to engage with the secondary sear and so lock the hammer back. In this case, the trigger bar needs to be repaired to restore the disconnector function.
With regard to the hammer dropping as the slide returns to battery, there are two tests you can perform (with an empty gun, of course):
Starting with the hammer dropped -
One - Cycle the slide while your finger is not on the trigger. If the hammer follows the slide forward, the sear engagement is too little. If the hammer stays back (cocked), the sear engagement is probably OK (but if the engagement is marginal, the sear could still release under the battering of recoil).
Two - If the gun passes the first test, then cycle the slide while holding the trigger fully back. If the hammer does not cock but follows the slide forward, then suspect the disconnector has failed. You can observe the trigger bar by removing the left side grip.
Let us know what you find.
Regards,
Mike T.[/b]

IZH35M Sear setup

Posted: Sat Apr 08, 2006 3:54 pm
by diopter
I re-read the instructions that came with mine.
It dawn on me that what they were trying to say for setting up the sear engagement is:
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With empty pistol and grip safety off, turn sear screw(c) clockwise until hammer falls. Trigger should not be pressed during this stage.

Then back of the sear screw two complete turns counter clockwise for the MINIMUM safe sear engagement.
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Oil the sear.

I would also use a spray crud cleaner in the sear/hammer frame area and use a pull through to clean up any lead and wax in the chamber.

Mine works fairly well this way.

I have an ocassional double when I press the trigger too hard.

Doubling and Full Auto Malfunctions

Posted: Mon Apr 10, 2006 11:18 am
by nthe10ring
I bought my pistol several years ago and had it double on the very first clip. I tried several types of ammunition but would still have the occasional double and on a few occasions it went full auto. I had the dealer that i purchased it from send it back to EAA for repairs. They repaired the gun and had it back in a week and it will shoot anything you want to put into it with no problems. The repair was to take a few thousands off the breech face increasing head space. These guns are set up to shoot the very thin rimmed steel case 22 Russian ammo and the headspace is a bit small for the ammo that is available in this country. I have put literally thousands of rounds through the pistol since then without the first sign of a malfunction.

Posted: Tue Apr 11, 2006 12:12 am
by 22dude
I backed off of my sear adjustment, increased the trigger weight, scraped any place that might have a burr and put a thicker oil on the firing pin (which was sliding back and forth freely). I shot over 200 rounds today and no spray and prey. Now which one actually fixed the issue I'm not sure, but I would guess the sear engagment was the culprit. Thanks for the replys.

Do you think EAA would adjust head space on a second hand Pistol?

Posted: Tue Apr 11, 2006 12:31 am
by 22dude
I also discovered that it shoots a lot tighter groups with Wolf MT and ME than with all things Eley (pistol standard, pistol target and pistol match) and CCI (sv and Green Tag). This was from a sand bag at 50 yards. .860" with Wolf and up to 6" with Eley.