A friend of mine has received a sks that I personally experienced it slamfire when it was owned by a 3rd party , i then didn't know anything about the sks and i am def no expert now but have learned that its caused by the weight of the firing pin inertia when the bolt slams shut . My question is , is there a fix for this ? thanks
SKS slam fireing question
- Thread starter Eugene L
- Start date
I've only ever seen it on a gummy (read, still full of cosmoline) bolt and/or a rusty firing pin. I would start by completely disassembling the bolt and making sure the pin and associated parts are spotless. Make sure when you reassemble it that you shake it and can hear the pin freely moving back and forth. There is/was a firing pin spring that could be installed, but proper maintenance should make this feature redundant
Oh, just thought too. Commercial ammo? Reloads? Because of the softer primer on those than milsurp, it can be a little easier to strike off, but still shouldn't happen with a proper functioning bolt
Oh, just thought too. Commercial ammo? Reloads? Because of the softer primer on those than milsurp, it can be a little easier to strike off, but still shouldn't happen with a proper functioning bolt
https://murraysguns.com/sks-firing-pins/
A good cleaning might be enough, Mind you, trigger problems may produce similar symptoms.
A good cleaning might be enough, Mind you, trigger problems may produce similar symptoms.
Slam fires in the sks are cause by two things.
1. Stuck and protruding firing pin--either from grime or a broken pin. If the fp channel isn't compromised, this can be fixed with a cleaning or a new firing pin or both if needed.
or
2. Inadequate friction between the hammer bearing surfaces-- this loss of friction can be caused by heavy use or most likely (imho) DIY home trigger jobs. The sks uses a friction safety-- no hammer block, or transfer bar etc. Modifying the friction between the hammer bearing surfaces to "improve" the trigger pull, has a direct effect on the functioning of the safety and can also lead to slam fires. To fix: replace the trigger or send your trigger assembly to a qualified smith familiar with the sks like Kivaari or Murray's.
gewehr76
CGN Ultra frequent flyer
As mentioned above slam fires can occur when reloaded or commercial ammo with soft primers is used. Due to free-floating firing pin design, the ammo could be set off by the fp inertia. So check what kind of ammo is used or try some surplus ammo first before doing disassembly.
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Stuck firing pin, caused by oil/dirty gummed up firing pin channel. A good cleaning solves it, the pin should rattle back and forth when you shake the bolt.
Commercial primers can be the cause of it, they are softer than milsurp primers. If you load a modern commercial round and drop the bolt fully from the rear and then eject the round with firing you will usually see a slight dimple on the primer as the firing pin hits it when the bolt closes. I’ve seen slam fires with 2 and 3 shells on either PPU sp or Hornady SST’s.
Commercial primers can be the cause of it, they are softer than milsurp primers. If you load a modern commercial round and drop the bolt fully from the rear and then eject the round with firing you will usually see a slight dimple on the primer as the firing pin hits it when the bolt closes. I’ve seen slam fires with 2 and 3 shells on either PPU sp or Hornady SST’s.
Just a note re 'sticky FP' - I bought some 'wire bristle' pipe-cleaners from amazon.ca - a few bucks for 300-ish. They are stiff and have the bristle to help remove 'sticky crap', I just dip in solvent like Hoppes and run thru FP-channel (after removing the FP, of course).
BTW I've never let any of my SKSs get so dirty as to 'stick' - but I've never shot more that 2-300 rounds of Mil-surp OR 'Factory' ammo w/o cleaning (on the same day). I clean after every use - just an extra 15 min the break down and run hot water thru it all. And check for "rattle".
BTW I've never let any of my SKSs get so dirty as to 'stick' - but I've never shot more that 2-300 rounds of Mil-surp OR 'Factory' ammo w/o cleaning (on the same day). I clean after every use - just an extra 15 min the break down and run hot water thru it all. And check for "rattle".
JH, that's true . . . and why I tear down any rifle new2me . Even if it's used - or especially if it's used . . .
Here's the cleaners I've got > but they were only $5-6 when I bought them 2-3 years ago . . .
http s://www.amazon.ca/Zen-Bundles-Cleaners-Bristle-Count/dp/B07BH7WYXZ/ref=sr_1_4?crid=34W60TAZWY75D&keywords=pipe+cleaner+hard+bristle&qid=1687801765&sprefix=pipe+cleaner%2Caps%2C121&sr=8-4
Here's the cleaners I've got > but they were only $5-6 when I bought them 2-3 years ago . . .
http s://www.amazon.ca/Zen-Bundles-Cleaners-Bristle-Count/dp/B07BH7WYXZ/ref=sr_1_4?crid=34W60TAZWY75D&keywords=pipe+cleaner+hard+bristle&qid=1687801765&sprefix=pipe+cleaner%2Caps%2C121&sr=8-4
If your buddy doesn't want to go to the extent of taking the bolt apart buy a can of brake rotor cleaner and do this outside hold the bolt with rubber gloves on and blast the cleaner through the bolt . wear safety glasses . you should be able to hear and see the firing pin slam back and forth loose. unless it's the year 1949 1950 and I think some or 1951. in that case you might have to disassemble the bolt . there is a spring in these years.
This.
Even with a clean gun it is not uncommon to see a dimple on an unfired primer cup; apparently - compared to military commercial-grade primers tend to have softer primer cups.
The practical solution is to clean it, and to use military-spec ammunition with military-spec primer cups, and to control your muzzle at all times.
There once was an aftermarket kit available (in the USA) that would enable you to convert an SKS bolt to a rebounding firing pin, but I don't see the kits available anywhere, and in any case such a conversion is probably unnecessary - provided, of course, that you clean your gun and control your muzzle.
Brownells still sells the Murrays FP with a spring, but they'll end up ca $100 CDN (OR MORE?) and you need an import license !
As many have said, just clean the FP and channel - it only adds 5-min to regular cleaning. You could just spray-clean but I prefer 'Real' cleaning - "...the only way to be sure ! "
As many have said, just clean the FP and channel - it only adds 5-min to regular cleaning. You could just spray-clean but I prefer 'Real' cleaning - "...the only way to be sure ! "
Or immerse it in a cup of gasoline or varsol, leave for a while then shake it around and re immerse. Do it a couple of times until there is no dark gunk coming out.
Thanks for the info, i will pass it along , good chance it could of been a combination of all the above, the owner at the time wassnt the type to go apast cleaning the barrel and spray wd 40 on the bolt , I know he will go threw it hard core cleaningand polishing all the contact surfaces.
I ordered the Murray's firing pin directly from their site and got it like a week later in the mail with zero problems not sure what your going on about
