Triggers & Systems Explained

    First let’s talk about the different types of trigger pull systems.  We’ll start with the oldest and most fundamental: Single Action.  

Single Action trigger systems do exactly what the name implies.  It does a single action, namely, disengages the sear (the part that holds the firearm from firing) from the hammer, releasing the hammer, allowing it to fall, causing ignition.  If you’ve ever watched an old western movie or TV show you’ve seen guys and gals wielding single action revolvers.  With single action revolvers once the hammer falls, that’s it.  Everything the mechanism is designed to do is done.  That means to reinitialize the system you have to manually cock the firearm by pulling the hammer back until the firearm is cocked, making it ready to fire again.  

    The next system that was developed and is still very popular today is double-action systems.  With double-action systems the hammer on the firearm is normally down, in the un-cocked position.  When you pull the trigger, the trigger causes the hammer to rotate back until a certain point at which with your continued pulling of the trigger the hammer is released and ignition occurs.  If you’ve seen British WWI movies where an officer is firing a revolver, chances are he was firing a double-action revolver.  But we’re not done. 

 

    And there are two types of trigger/sear systems.  There is single-stage and double-stage.  Single stage is normally the most adjustable, smoothest, least creepy (see my article on trigger jobs), and lightest trigger system.  Doubles are the opposite.  The overall design of the firearm often dictates which system a manufacturer uses.  If you have a choice I’d just about always suggest a single-stage versus a double stage for pistols or revolvers.  Not the same for rifles or shotguns.  Many rifles and semi-automatic shotguns use double-stage trigger/sear systems.  And that brings us to semi-automatic pistols. 

 

    Here things get more complicated.  First we’ll just talk about the semi-automatic function and to do that we’ll consider an automatic firearm first.  Automatic firearms are those where once the hammer is cocked, when you pull and hold the trigger the firearm will keep firing.  All you have to do is hold the trigger and bullets keep coming, one right after the other.  Semi-automatics are firearms where when you pull the trigger one bullet is fired AND the pistol loads another round and cocks the hammer.  Continued pulling of the trigger will not fire another round.  Once you release the trigger an internal part called a disconnector will allow the trigger to be reconnected (yea, I know, why not a reconnector, right?) to the fire control mechanism such that when you next pull the trigger the firearm will fire and the cycle will repeat.  

    Just to add to the confusion there are two kinds of semi-automatics!There are semi-automatics – just the name semi-automatic we’ve already described.  Then there are double-action and double-action only semi-automatics!double-action only Semi-automatics act just like double-action only revolvers.  When you pull the trigger your finger pull causes the hammer to be pushed back until it releases and fires the gun.  Of course the difference between a semi-auto and a revolver is when you pull the trigger on a revolver you are also causing the cylinder to rotate a new round into alignment with the barrel before firing and with a semi-automatic part of the recoil of the firearm is used to load a new round into the barrel in preparation for the next trigger pull.  Unlike a double-action only semi-automatic a double-action semi-automatic uses the first trigger pull as a double-action pull just like a double-action only, but then becomes a semi-automatic.  The first pull is long and harder than all the remaining pulls.   The first round fires and some of that energy is expended to cock the hammer for the next round.  

    I won’t confuse you even more but will mention there are other types though they are found primarily on antique or special use firearms.  

    Thought you were done?  Hah!  We haven’t talked about the two primary fire-control systems in use.  The fire control systems is a combination of the trigger and all the other parts that cause the round to ignite.  They all have a trigger of some sort of course.  But then we have two types of mechanisms the trigger would be attached to.  There are hammer-fired and striker-fired mechanisms.  I don’t know of any striker fired revolvers and can’t imagine how one would make one either.  But semi-automatics come in both flavors.  And both systems have been used for at least one hundred years.  Most “modern” designed polymer (plastic) guns (they actually have metal frames the plastic is attached to) and some rifles are striker fired.  Opinions vary and I’ll offer my own observation and opinion.  Although most new designs are striker fired, they have several disadvantages and only one advantage to hammer-fired mechanisms.  The one advantage is that there is no hammer sticking out anywhere to get hung on your pants or purse.  

The advantages are several.  

Unlike a striker fired (and I know of one striker fired that is an exception), with a hammer fired mechanism if the firearm doesn’t fire for some reason you can always pull the hammer back and try again with the same round.  With a striker fired you MUST rack the slide and eject the round before you can try to fire again and you can’t try that round again unless you reload it into the magazine.  

Second, because of the way many striker fired guns are constructed internally the trigger is not attached to the striker mechanism inline with the center of the trigger.  In fact there may be several “arms” attached to the trigger that make their way to the striker mechanism.  These two factors mean the trigger pull is not as crisp and there is a higher propensity for the trigger to be soft, squishy, or creepy.  It may not be when new in the box but if you fire it a lot there is a higher probability of developing any or all of these problems.  Last, one more advantage to a hammer fired mechanism is that if you choose to keep a round in the chamber and the hammer down, to fire the firearm you only have to pull the hammer back to cock the gun.  With a striker fired you have to rack the slide.  If, for some reason, one of your hands is injured, say when you are being attacked, it is really hard to rack the slide with only one hand.  You have a higher probability of getting that hammer pulled than racking the slide.  Don’t get me wrong – there are ways to rack a slide one-handed and if your practice at it and have the right environment it’s possible.  Oh, and say you are a woman or elderly.  Racking a slide takes some strength.  Cocking a hammer – not so much.  

    And if that isn’t confusing there are hammer-fired guns with the hammer hidden internal to the firearm so you can’t get at it!]

    Why have I treated you to all this stuff?Because these are things you need to consider when purchasing a handgun.  AND I believe if you are aware of how complicated this all is you will better appreciate how you are better served by getting recommendations from someone who isn’t a salesman but a gunsmith in making your purchase decision.  

 

   When you come to see me to purchase a handgun I will have a number of questions to ask you.  Then I’ll have you hold different firearms to see which one literally “fits” your hand.  And unless you are a middle-aged man or younger I’m going to have you rack slides to make sure what you are purchasing is something you can actually operate!