Contribution from Bapegg
Here is how I remove OEM trigger shoes without damaging them.
Tools that you will need are a hammer, 1/16" drive pin punch, straight mechanics pick, armorer's block (or similar) and optional is a countersink.
Step one is to drive the pin into the shoe with the 1/16" punch. You only want to drive it until there is a small raised area on the opposite side showing where the pin is. CAUTION - do not drive the pin through too much or it will break out the side of the trigger shoe.
Second step is to flip the shoe over onto your pin block. You then center up the mechanics pick on the raised area and tap the pick with your hammer until the pin comes out far enough to remove the trigger bar. I like to drive the pick far enough to open up the pin hole most of the way.
Once the pin is driven out completely (using the 1/16" punch) I like to chamfer the hole using my countersink.
The countersink is 1/2" 82 degree. I also use it on the frame after drilling all the pin holes. I only turn it by hand so that it does not dig into the soft polymer too much.
I'll run the 1/16" punch and the trigger shoe pin through the hole to clean it up afterwards. As long as you take your time and do not try to drive the pin out too much through the blind side, you will not break the shoe and it will be reusable.
Basic information on what can cause bad sear engagement & how to fix it. Some of the more common causes are as follows:
Aftermarket trigger bars that are out of spec.
Aftermarket trigger housing that are out of spec.
Aftermarket strikers that are out of spec.
Rear rails sitting too high in the frame.
Rear holes drilled wrong.
Front and rear rails not level to each other and to the frame.
Aftermarket slides cut out of spec.
Here are ways to fix the issues:
The best fix is to use all OEM parts.
Make sure that the front and rear rails are level to the frame and to each other and also sitting at the correct height within the frame.
It has been found that using a modified Gen 4 trigger housing in place of the Gen 3 trigger housing does improve sear engagement on some frames.
One of the biggest mistakes I see is people not properly fitting both front and rear rails to the frame. Another big mistakes is when people open up the holes in either the rails or frame. Take the time to properly fit the rails to the frame. Yes opening up any of the pin holes will only lead to other issues.
Another fix which I will never recommend is to bend the cruciform in a vice or with pliers. Yes it can be done, but you risk bending it too much along with breaking it. Which leads to the next mistake I see people make. NEVER under any circumstances heat up the trigger bar to bend it. You will ruin the trigger bar by doing so and make your pistol unsafe to use.
Now for a short lesson in metallurgy and why one should NEVER heat up the trigger bar. Heating the trigger bar can do one of two things. You will either change the hardness and make the bar brittle or you will change the temper and make it softer (bend easier).
Making the trigger bar harder will allow it to break more easily.
Hardening steel is done by heating it up until it is glowing cherry red. And the thinner the metal is, the less heat it takes to get to temperature.
Changing the temper and making it softer will allow it to bend under normal use.
Tempering steel is done by heating the metal until it just starts to change color to a golden brown straw color. This actually softens the steel. Again, the thinner the metal, the less heat required.
Some steel , depending on composition, can be tempered at temperatures as low as 275 degrees.
Heating the trigger bar until it is too hot to touch but it isn't starting to change colors does nothing to the hardness or temper and is a total waste of time. It will not make the cruciform any easier to bend.
All of the above information is based on 30+ years as a machinist/tool and die maker and having to heat treat/temper numerous types of steel in those 30+ years.
Now if changing out parts to include a bad slide does not fix your sear engagement issues, You really need to double check your frame, rails and pin holes. No amount of swapping parts will fix things if the pin holes, rails, or frame are messed up.
I hope this information helps everyone to fix bad sear engagements. It is your safety on the line so please make the correct repairs.
We are going to talk about opening up the pin holes in the front locking block (FLBR) and in the rear rail (RR) along with the pin holes in the frame itself. And most importantly why you should NEVER open them up.
Glock and Polymer 80 have designed/engineered the frames, rails, and parts to tight tolerances so that everything works together. All of the pin holes must be in the correct position and the correct size to insure a safe and reliable firearm. The pin holes are placed exactly where they need to be and to the correct size so that all parts fit together and function safely.
We all know that Polymer 80's quality control does leave room for improvement when it comes to the FLBR and RR. It is required to hand fit both the FLBR and RR to fit into the frame correctly and for the pin holes to line up like they should. There are quite a few threads and videos explaining how to properly fit the FLBR and RR.
The reasons that you should never open up pin holes is that it will lead to other problems/issues with your build. Opening up pin holes in the FLBR, RR, or frame can and will cause the rails to not sit in the frame correctly or allow them to move when the pistol is fired. All of which can cause problems with how the slide moves, how the rounds load, or sear engagement issues (not resetting or hard trigger pull).
Too many times people ask for help with issues only to find out they did open up pin holes. A properly fitted FLBR and/or RR would have not caused such issues. I know that in some of the early videos MGB did mention opening up pin holes. From a machinist/tool and die maker/gun smith background, I can say that is bad information and should NOT be done. By no means is this meant as disrespect towards MGB, he does know his stuff.
If you are still having issues getting the pin holes to line up after properly hand fitting the FLBR and RR, then something is out of spec. Most of the times it is the FLBR and/or RR that is bad and you will need a replacement. Other times the holes have either been drilled wrong, oversized (due to bad bits), or the jig itself is out of specs.
IF you use the correct drill bits that are sharp and ran at the correct speed, you should not have issues with the pin holes in the frame. Take your time hand fitting the FLBR and RR to insure that the pin holes line up with the holes in the frame. I have yet to find a FLBR or RR that could not be hand fitted or require the pin holes to be opened up.
Save yourself the headaches by taking your time and doing things correctly the first time. FTQ is just as much a mind set as it is a method.
Now for some background info on me. I am a retired machinist/tool and die maker/gun smith. I have built everything from weapon systems in the Army, to making precise investment cast molds to precise stamping dies used to manufacture parts, and industrial machines. No I am not perfect and I still learn new stuff everyday. To include learning things from other members here on the forum.
In the end, do not hesitate to stop and ask questions if you are unsure. Don't let pride/ego get in the way of building a FTQ pistol that is fully 100% functioning and safe.
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