OVERVIEW:  Here and again you hear folks complain of slamfires while enjoying their SKS.  I didn't realize how prolific it was until I ran a recent poll to determine how frequently this occurs.  SLAMFIRE POLL:  Out of 145 responses, 76% of you have NEVER had a slamfire (I'm in this group).  8% doubled one time only (one time too many?), 9% once or twice, and 7% have had several on several different occasions.  The poll is by no means scientific, but it's a fairly decent indicator.  This means:  1 in four SKS owners can pretty much expect a slamfire at some point.  Approx 1 in 10 are going to have serious slamfire problems.  This merits further discussion...

What is a slamfire?

A slamfire is when the rifle unintentionally discharges when the action cycles.  This is caused by the firing pin protruding from the bolt face and engaging the primer before the trigger is pulled.  A slamfire can be as simple as pulling the trigger and two shots go off instead of one.  This is commonly referred to as doubling.  It can also be as dangerous as casually chambering a round with a loose grip on the rifle and it instantly discharges, fully automatic, emptying the magazine.  Not only is the shooter caught off guard, but even experienced Class III shooters have trouble controlling fully automatic fire with two hands, never mind one handed.  More than one person has died because of this extremely rare occurrence.

What causes slamfires?

There are three main culprits in isolating a slamfire.  The following are arranged in the order of most common to least common:

• INERTIA (MOST COMMON, MOSTLY RESPONSIBLE FOR DOUBLING):  Other than first year Russian SKS's, the firing pin on an SKS is free floating.  This means the pin does not have a return spring and moves freely inside the bolt.  When the bolt carrier is drawn back fully and released, the bolt carrier slams against the receiver, which catches the bolt.  Much like a person not wearing a seatbelt in a collision, even though the bolt is stopped, the firing pin maintains forward momentum until it strikes the primer of the newly chambered round.  This impact is usually not enough to discharge the round, but sometimes it is.  SKS's were developed for the Russian military using Russian military primers which are much harder than today's domestic primers.  Therefore the main spring could be stiffer and the firing pin can be heavier and no problems will result.  However, with today's thin walled primers, simply chambering a round can leave behind a significantly large (and quite scary) dent behind.  Try it sometime at the range.  Point your rifle safely downrange, secure the rifle, and chamber a round.  Now cycle the action again, chambering another without firing the first.  Examine the primer of the ejected round.  Is it simply scratched, or is it cratered?    

• JAMMED FIRING PIN (MOSTLY RESPONSIBLE FOR EMPTYING MAGAZINES):  There is one main reasons why a firing pin gets jammed in the bolt:  improper maintenance.  If the bolt is filled with cosmoline and fired, the burnt powder and grit turns the cosmoline into an even thicker paste.  Eventually, the paste gets so hard and baked in that it freezes the firing pin in the full forward position.  A clean, oil free bolt is a must.  However, the best intentions can work against a shooter.  While cleaning the bolt assembly, did you properly reinsert the pin?  Some Chinese firing pins can be inserted upside down, so when the retaining pin is replaced it jams the pin forward.  Perhaps the firing pin was accidentally bent while out of the rifle.  This can jam the pin as well.  A properly cleaned and maintained firing pin should rattle inside the bolt and fully retract when correctly reassembled.   

• FAULTY TRIGGER GROUP (MOSTLY RESPONSIBLE FOR DISCHARGES WHILE COCKING):  Sometimes, parts of the trigger assembly (especially around the sear) are either worn out or improperly built in the first place.  This will prevent the hammer from locking in the full back position when the bolt forces it down.  When the bolt flies forward, the hammer is released, following right behind, discharging the round just as if the trigger was pulled.  The only solution to this problem is to send off your trigger group to be overhauled.

What can we do to prevent slamfires?

Well, first off, most people don't have a slamfire problem.  If you do have a problem, all but the INERTIA problems are readily correctible.  So what can we do about inertia?  Lighten the firing pin.  Even if you are like me and don't have slamfires, it would probably be a very good idea to lighten the firing pin anyway.  

There is a man I know who feels passionately about this topic topic by the name of Dr. Gene Neill.  In out many heated discussions about this topic, Dr. Neill suggests two ways to accomplish this:  a titanium firing pin (similar to the ones found in the AR-15 and other quality rifles) or lightening the existing pin by removing metal (strategically drilling holes).  

I'm a big fan of the lighter firing pin, unfortunately none exist.  It's my assertion that one could take a micrometer and measure the four most common firing pins (late Russian, both Chinese, and the Romanian) looking for consistencies in all of them.  At that point, a universal firing pin can be designed with these measurements, turned in a lathe, and sold to those who desire them.

So there it is.  The answer to inertia slamfires which doesn't limit the sportsman to one brand of ammunition, is a drop in solution which will not reduce the resale value of the rifle or require any special tools, and a brand new business in a wide open niche market.  Every SKS owner should have a titanium pin.

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