Disassembly/Reassembly of Your STI/SV Gun

by Bob Londrigan, published in Front Sight Magazine, Jan 2005

Customers bring up the same question over and over again:  "How do I take my new gun apart and put it back together?"  That’s what I am going to address in this issue.  I am going to explain how to take your gun down to the very last piece (or at least as far as you should ever go), give it a good cleaning, and then reassemble it.  Most of the time, simply cleaning the top end and wiping down the bottom end will suffice.   However, every once in a while you need to take your gun down completely to clean out the accumulated gunk. 

The instructions I provide here apply to both open and limited guns.  I’ll point out any differences between the two as we encounter them.  Although the directions pertain to STI/SV guns, most will also work with any 1911-style gun.

Since springs and things may take off on you as you disassemble/reassemble your pistol, always wear safety glasses when working on your gun.  Another tip that will help with reassembly is to lay the parts out on your bench in the order you take them out of the gun. Then you just reverse the order when you put the gun back together – it keeps you from searching for parts.

Begin the disassembly procedure by making sure your gun is unloaded.  Once your gun is unloaded, rack the slide back and lock it with the slide stop.  Insert a takedown tool in the hole provided in the guide rod for this purpose.  The takedown tool is simply a paper clip with a 1/8-inch bend at the end.  If you’re using a RecoilMaster in your STI gun, you will need a special takedown tool as shown in the picture on the open gun. 


If your gun has a slide racker, take it off before starting the next step. With the takedown tool in place, slowly release the slide until it touches the takedown tool.  Once the guide rod plug/spring is captured remove your slide stop by lining it up with the removal slot in the slide.  Now the entire slide/barrel assembly will slide off the top of the frame towards the front. 

Next, take the recoil guide rod system out of the slide while leaving the spring and plug captured. You may have to roll the barrel link towards the rear to get this assembly out.  Relieve pressure on the spring carefully, remove the takedown tool, and slowly release the guide rod plug.  Now just slide the barrel out the front of the slide making sure you have the barrel link rolled toward the front.

Continue by using a punch to push in the firing pin and then remove both the firing pin stop and the firing pin.  Make sure you keep the firing pin under control as it tends to go flying.

Next comes the extractor.  There are two types in use today:  the standard extractor and the Aftec extractor.  To remove a standard extractor, use your punch to push the hook portion of the extractor towards the rear of the gun.  This ensures the hook has cleared the breechface before you try to remove it.  Once the hook has cleared the breechface, use the punch to pry the extractor out from the rear. This procedure is a little different for the Aftec because the Aftec has a few small springs you need to contend with.  As you would with a standard extractor, start by pushing the Aftec until it clears the breechface.  Now rotate the extractor 180 degrees and then pull it out slowly until you see the spring cap (it should be facing you at this point).  Slowly remove the extractor the rest of the way while holding the spring cap to prevent release of the springs. Sit back and take a deep breath -- you have completely disassembled your top end.



On to the bottom end -- begin by taking the thumb safety apart.  First cock the hammer, then move the left safety lever (viewed from the rear) up until it is in the sweet spot.  The “sweet spot” is about half way on safe, usually when the corner of the safety is even with the detent (see picture for approximate location.) 


Wiggle the safety back and forth as you proceed to pull it out.  If it is particularly tight, tap it from the side with a hammer or get behind it with a thin blade and pry it out.  Once this side of the safety is out, lower the hammer gently.  Next remove the magwell by using a punch to take out the mainspring housing pin.  You are now able to take off the mainspring housing, sear spring, hammer, and sear/disconnector in that order.  The hammer and sear/disconnector are each held in place by a pin. These pins should easily push out. Also remove the safety spring plunger assembly at this time.

This is normally as far as you need to go in disassembling the bottom end.  However, about every 5,000 rounds or so, you need to take the disassembly/cleaning process a little further.  This involves disassembling the mainspring housing, removing the magazine release, and taking off the grip.

To disassemble the mainspring housing, use a punch to push down on the mainspring cap and remove pressure, use a small punch to push in the mainspring cap retaining pin, and then slowly let the mainspring cap out of the mainspring housing.  The cap is under a lot of tension so be sure it doesn’t get away from you.

Now you’ll need to remove the magazine release.  If you have a button attached to the release, remove that first.  Next turn the mag catch release (small screw in the mag release) counterclockwise while you depress the mag release about 1/8 inch. There is a sweet spot here also so feel for it.  You should not have to apply force to turn the mag catch release.  Once turned, you are able to slide the mag catch out of the grip towards you.

Lastly, you remove the grip.  The grip is secured to the frame by two screws in the middle of the grip (one on each side) and two screws at the front of the trigger guard.  Do not remove the lower screws as they are meant to be permanently attached.  First, remove the two screws in the middle of the grip.    These screws are screwed into removable bushings in the frame that must also be taken out to remove the grip. Tap the bushings toward the inside of the grip with a punch and they should fall through.    Now let’s move on to the screws in front of the trigger guard. Place a hex key in each of the two screws and unscrew – one screw comes out while the other remains in the center bushing. Do not remove this screw from the bushing.  Simply punch the bushing out from the opposite side.  You now should be able to remove the grip by rocking it back and forth a little or by tapping the frame slightly little with a rubber mallet.  Once the grip is off, the trigger slides out the back.

Now that everything is disassembled, clean all the parts thoroughly and check them closely for cracks.  Take a hard look at the grip since it is not going to be off the frame very often, and it is much easier to see a crack while it is off the frame.


The next challenge is to reassemble your pile of parts and restore them to a well functioning pistol.  Put the parts back together in the reverse order from disassembly.  As you reassemble the gun, make sure each part goes back in easily and that things slide back and forth the way they should.  For instance, there should be no drag between the trigger and the frame, the hammer and sear pins should not bind, etc.  If you get some bind, check for stray particles of gunpowder or dirt that have worked their way into the mechanism. 

Here are a few tricks to remember when reassembling your gun:

When you are putting on the mainspring housing, first set the sear spring in its channel, now push the mainspring housing on about a third of the way, and then check the sear spring legs for proper engagement with the sear and disconnector.  Replace the grip safety and hold it in place on the right side while you slide the mainspring housing on the remainder of the way.  This will prevent the left sear spring leg from slipping off the sear (a common problem).  Replace the magwell and magwell pin.  Now cock the hammer and pull the trigger while holding the hammer to prevent it from falling and damaging the frame.  This is a final check before you get everything buttoned up to make sure the sear, hammer, and sear spring all are functioning properly.

You can now replace the left side of the safety.  Remember to cock the hammer first and make sure it goes back in the sweet spot.  Also don’t forget to replace the safety spring plunger.

Next put together the slide – again, just reverse the order of disassembly.  Once the slide is together, put the barrel back in as well as the recoil spring/guide rod assembly.  The top end should slide onto the bottom and line up with the slide stop with the takedown detent in the slide.  Make sure the link is visible through the slide stop hole in the frame and then insert the slide stop.  Lock your slide back, remove the takedown tool, and slowly release your slide.  Congratulations you have successfully re-assembled your pistol.

If it looks like a gun, then it should function like a gun.  Nonetheless, please don’t try this procedure for the first time the night before a big match.  Always leave yourself at least one practice session after you have put your pistol back together to make sure everything runs right.

1911 parts at Brazos Custom