Tag Archives: Polymer80

How to Check A Polymer80 Or Glock’s Firing Pin Strike

One of the challenges when you are working on a firearm is trying to figure out what is going on in spaces you can’t directly observe. The Polymer80 frames given an awesome platform to build a custom pistol but you have the challenge of wondering just how hard the firing pin will strike the primer. I know a bunch of you load a round and test fire but that is not an option where I live now so I had to figure out an alternative.

The internals of a Glock reflect pure genius on the part of Gaston Glock. How he figured it all out is beyond me and the best I can do it is look at the parts and the functioning and draw conclusions about what is going on. Obviously a lot has to happen to release the firing pin and have it travel forward with sufficient force to strike the primer and trigger ignition. All sorts of stuff can go wrong and cause a light strike that then results in erratic firing.

So, I was sitting and wondering how I could test the strike in my shop. I started thinking about what I could put down the barrel that would get hit by the pin and both move reflecting the degree of force and also get dented so I could see depth, etc. My answer? A 5/16″ hardwood dowel and we do make and sell these.

Here’s a new 6″ test rod next to a Polymer80 G34.
Look at how it’s nice and clean – no dents and also no stray fibers/slivers that will catch on the barrel.

How To Test

First and foremost, visually inspect the pistol and don’t assume anything. Make absolutely sure the weapon is clear – that there is no ammunition in the chamber or a loaded magazine. Life is going to suck in the next part if you pull the trigger and the pistol is loaded so make sure it isn’t!!

Okay, hold the pistol vertical, drop the dowel down the barrel and pull the trigger. The dowel should to shoot up about 2-3 feet in the air depending on what springs you are using. The stronger the spring, the further the dowel will go.

Try this with some known good pistols first to get a feel for how far the dowel pops up. If a 5/16″x6″ dowel doesn’t even leave the barrel then you know you have a problem.

Here’s the dowel sticking out the end.

Now, the second part of the diagnostic is to look at the divot in the end. There should be a clear indent in the wood. Look at this next photo:

That dent was made by the firing pin hitting the wood and is from my PF940CL pistol that works great plus it’s also running a full power OEM Glock firing pin spring. It makes a much more pronounced dent that my G34 which is running a reduced weight Glockmeister firing pin spring.

This method has worked very well for me as I can repeatedly test fire with the dowel to diagnose light strikes without constantly needing to shoot live ammo.

I hope this little trick helps you out as well. Again, we do sell these if you are interested – click here for our store.


If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



How To Install a Polymer80 or Glock FIring Pin Channel Liner

When you buy a stripped slide for your Glock or Polymer80 build, you will find that you need to install a Firing Pin Channel Liner – Glock part number 1148. For some reason this worries a lot of folks but it is actually extremely easy to install.

This small plastic tube is the firing pin channel liner. Please note it is solid – the tube with a channel in it is the firing pin spacer sleeve so don’t confuse the two. Also, please note this has two different ends – the left end is beveled and is what goes into the slide. The right side has a straight edge and this is what will rest on the shoulder of the installation tool.

Do I really need it?

This question pops up from guys who feel intimidated by having to install the liner. The short answer is, “Yes, you do really need it”. The liner serves a couple of purposes. First, it is a buffer that isolates the firing pin from the steel slide so you do not have metal on metal wear. Second, because the system was designed with that spacer, leaving it out will cause alignment problems. Note, stick with OEM Glock plastic liners. I’m not recommending brass, stainless, etc.

Do I need a tool?

I’d recommend it and they are dirt cheap. Basically the tools are a metal rod with a shoulder. The channel liner slides on and you tap it into place. Some are threaded to enable removal. I use the following simple tool for installation:

Ok, how do I install the liner?

The first step is to inspect the channel liner. On the end with the straight cut you will usually see some waste plastic, known as “sprue”, left over from the casting process. Use a razor blade or sharp knife and just cut that off so it doesn’t hang on anything or get in the way.

See that little piece of waste plastic sticking out on the top? Just cut it off flush with a razor or a sharp knife. You cal also see how this is the straight end of the liner that will sit against the shoulder of the installation tool.
This photo isn’t as crisp but hopefully you can see the slight bevel on this end of the liner. This is the end that will go into the slide.

Slide the liner onto the tool. The straight cut edge rests on the shoulder of your tool.

Slide the liner onto the tool with the bevel facing out and the straight edge against the shoulder.

Then you insert the liner into the big hole in the rear of the slide. You and usually push it a bit of the way. Rest the nose of the slide on your bench and tap lightly with a small hammer. You will hear and feel the difference when the liner is seated all the way. It really is that easy.

This is just so you can see the orientation of the tool. I rest the nose of the slide on my bench block and tap the tool with the a small ball peen hammer to seat the liner. I had to use the vise purely to take the photo.

A Video To Help

Brownells put together a real nice to-the-point video on how to do this:

Sources For Liners and Tools


The Glock firing pin channel liner is definitely nothing to fear and I hope this helps you out.



Note, I have to buy all of my parts – nothing here was paid for by sponsors, etc. I do make a small amount if you click on an ad and buy something but that is it. You’re getting my real opinion on stuff.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



The Correct Replacement Spring For the Polymer80 PF940CL Slide Lock

I’m a huge fan of the Polymer80 pistol frames. They are solid products with significant design improvements over their Glock counterparts that make me prefer them – notably the grip angle and the integral Picatinny rail under the barrel. Recently, I did a PF940CL and this is a unique design to them – it is like a Model 19 in terms of the grip length but the slide and internal parts are from a full size Gen 3 Model 17. The “CL” stands for “Compact Long”.

PF940CL Based Pistol

In reading the instructions, they noted the kit came with a special slide stop coil spring instead of the typical Glock 17 leaf-style and to be sure not to lose it. In looking at the little spring in the kit, I had no idea what it was and wanted to have a spare just in case. I can also imagine guys losing this little spring and needing a replacement as well.

I emailed Polymer80, asked what it was and they replied back that it is a Glock Gen 5 slide lock spring. Problem solved — Brownells carries those and I ordered in a couple of spares.

Glock Gen 5 Slide Lock Spring – click the image to go to the Brownells item listing.

I hope this helps you out. The following is in case you need other parts as well.


If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



Found a Very Good Video Series on Building A Polymer80 Pistol Plus Links To More Info

I like Polymer80 pistols – plain and simple. There are great deals on commercially built pistols that are hard to beat so I would not recommend building one to try and save money – I doubt you can get the combination of price and quality. With that said, if you want to build a custom pistol and be able to do exactly what you want, then the Polymer80 makes a lot of sense.

Related Posts:
Why I think Polymer80 pistols are so great
How to build a Polymer80 legally in Michigan
There are a ton of Polymer80-related parts on eBay
Three must-have simple upgrades to improve handling

Brownells is one of my favorite sources for gun parts, tools and supplies. They assembled the following series of videos on how to build your own custom Polymer80-based pistol. Please note the embedded videos are small. Once you click play, then click on the small square in the lower right corner of the video to see it full screen.

Step 1: How to mill a Polymer80 Frame

Related Posts:
Tips For Building Smooth Operating Polymer80 Glocks
The Best Step-By-Step Guide Book For Building Polymer80s
Two Good Videos On Preparing a PF940C (Compact) Frame

Step 2: Choosing a Trigger For a Polymer80 Pistol

Related Posts:
Finding Glock Gen 3 Lower Pistol Kits (LPKs) on eBay
Customizing the LPK with parts from eBay

Step 3: Assembling A Polymer80 Frame

Related Posts:
Great video on building a full-size PF940v2 pistol
Polymer80 build troubleshooting
Tips for building a smooth operating Polymer80 pistol
I really like SLR mag funnels

Step 4: Picking a Slide For Your Glock’s Polymer80

Related Link:
Click here to see slide listings on eBay currently

Step 5: Selecting A Barrel For A Polymer80 Pistol

Related Posts:
Finding barrels on eBay

Step 6: Choose A Sight For Your Polymer80 Build

Related Posts:
Upgrading to Truglo TFX Pro sights
This is a link to Glock sights on eBay

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



How To Find Barrels For Your Polymer80 Build on eBay

In my last few posts, I’ve covered OEM lower parts kits and customizing the parts in the lower. In this post, I’m going to switch to the slide area and cover barrels. Without a doubt, having the right barrel for what you want to do is a very important consideration. Now notice how I worded that – it depends on what you want to do. There are barrel built for reliability, with match tolerances, porting, threaded ends, extended barrels… it really depends on what you want.

When I built my first two Polymer80 pistols – a full size Glock 17 unit and a full size 34, I went with threaded match barrels from 80P Builder. They are both accurate with 115 and 124gr FMJ but I quickly realized the added length wasn’t really worth it for me at this point. The idea behind a threaded barrel is that it will allow you to thread on some type of suppressor or muzzle device. To do that, the barrel with the threading needs to stick out – in the case of the 17, it sticks out about 0.634″ inches.

The threaded barrel extends 0.634″ past the end of the slide in this Model 17 build.

You have to ask yourself – do you really need that sticking out if you want a pistol for concealed carry. With my 34, it is a combat pistol and length isn’t something I worry about. In fact, it is running a Tyrant Designs CNC T-Comp brake that does a remarkable job of keeping the pistol flat during rapid fire. The end of the day, the threading definitely gives you a ton of options with a little extra length and weight added.

The Tyrant CNC brake is both radical looking and effective. It’s found a permanent home on my first Polymer80 Model 34 build. You can see a hint of the front Tru Glo TFX Pro sight as well.

If you like the idea of reducing muzzle rise and some recoil reduction, another option for you is a ported barrel where the manufacturer of the barrel actually will either drill holes or machine slots into the end of the barrel to vent gasses. I’ve not used a ported barrel on my Polymer80 but I do have a cz.75 with a ported barrel and the porting definitely helps.

Another option is to go with a standard length barrel that is more or less flush with the end of the slide. My next 34 will have a Zaffiri match grade flush barrel that is fluted and has a deep crown to protect the end.

Bottom line, you have a ton of options in terms of functionality and looks that you can consider so spending some time thinking about.

Vendors I’ve Heard Good Things About

So, you can do plenty of reading on offerings from vendors. The options are amazing – length, twist rate, thickness, threaded, fluted, ported, color and so forth. Just make sure you get a generation 3 compatible barrel and it matches the model of pistol you are building. In researching barrels, the following have good reputations: Agency Arms, Faxon, Glock OEM, Killer Innovations, Lone Wolf, Silencerco, Storm Lake, Wilson Combat, Zaffiri and Zev. If you click on the vendor names previously listed, a dedicated tab will open showing current offerings on eBay, if there are any.

Current eBay Glock Barrel Listings

Note the following a real time listing of barrels for sale on eBay. Pay attention to the brand as there are a ton of no-name barrels being imported of varying quality. Also, if you are building a Polymer80, go for barrels that will work with Gen 3 Glocks just to be safe.

If you click on the following banners, you can see even more:

Glock 17 barrel postings:

Glock 19 barrel postings:

Glock barrels in general:

I hope this helps you out.


Note, I have to buy all of my parts – nothing here was paid for by sponsors, etc. I do make a small amount if you click on an ad and buy something but that is it. You’re getting my real opinion on stuff.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



Customizing The Lower Parts In A Polymer80 Frame Via eBay

In the last post, I recommended that builders new to Polymer80s either start with an OEM Lower Parts Kit (LPK) or at least have one just in case their aftermarket parts are out of spec or something fails. In this post we are going to talk about customizing these same parts.

When you look at a Glock Gen 3 LPK for the model of pistol you plan (17, 19, 34, etc.) the following tend to be the parts you need:

  • Slide stop lever with spring
  • Slide lock & spring
  • Magazine release & spring
  • Trigger with trigger bar
  • Trigger housing with ejector
  • Trigger spring
  • Trigger pin
  • Trigger housing pin
  • Connector (5 pound)

I have seen aftermarket parts on just about all of the above and it depends on what you are buying. For example, you may just decide to replace the trigger shoe and need everything else or you may buy an entire trigger group with everything except the pins. The point is that if you decide to customize some or all of the parts, make sure that you have eveything required – springs, pins, etc.

For example, on my PF940V2 full size frame configured like a Glock 34, I am using an Apex aftermarket trigger shoe and bar but everything else trigger related is OEM glock. On my PF940V2 configured like a Glock 17, I am running a Zev Fulcrum Adjustable Trigger Upgrade Kit that includes the whole trigger assembly, firing pin, springs and plunger. Which of the two is smoother? I manually polished the Apex very carefully and it is very smooth. The Fulcrum is dragging some and I need to polish it one of these days. For as much as I paid, I’m surprised that any polishing is needed but it is a light short pull though.

So, when you do your lower, think things through. I automatically go with an extended Glock slide stop found on a model 34, an extended slide lock, a Vickers extended magazine release, all stainless pins and the trigger is an “it depends”. On my next planned 34 build, I am going to mirror polish all of the OEM Glock parts and then decide where to go from there.

My Glock 34 build – Apex trigger shoe & bar, Glock 34 slide release, extended slide lock and Vikers extended magazine release. This combination works great for me.

A few eBay buyer tips for you:

  • Look at the number of transactions and rating of the seller. If they have less than 10 sales, your potential risk increases.
  • Stick to Gen 3 parts. Glock has been evolving their pistols for a while now and the Polymer80 frames are designed with Gen 3 models in mind.
  • Make sure the parts you are looking for match the model you are building. Not all parts are interchangeable across models.
  • If the deal is almost too good to be true, it probably is. For example, you’re not going to find a high-end assembled slide with barrel for $50. Sure there are used parts and good deals but there are also scams. This is another reason to look at the seller’s ratings.

Gen 3 Triggers

There are a ton of groups making replacement Glock triggers. I’ve used Apex and Zev personally but have also heard good reports about Agency Arms, Overwatch Precision and Velocity Arms. Please note if you click on one of the previous names, a new tab will open with a dedicated search for that brand of trigger will open. With the triggers, you definitely need to pay attention to what comes with your purchase and what else you will still need to source. The following is a generic search on Glock Gen 3 Triggers:

Gen 3 Pins

You have the option of using Glock OEM pins or aftermarket. Now many will tell you that the polymer trigger housing pin is just fine and is proven. I had the polymer pin snap during a range session with my Polymer80 Glock 17 that has a Zev Fulcrum trigger. Why, I don’t know but I only use stainless pins now. I’m running pins from GunTools.

Glock Factory Gen 3 Extended Slide Stop (Release)

I have big hands and really prefer a slide stop lever that sticks out just a bit more than the flush fitting original. I use the OEM Glock Factory extended slide stop unit now and it’s way easier for me to operate without being obnoxiously large.

Gen 3 Extended Slide Lock

The OEM slide lock is too small for me. I have big hands and not a lot of feeling at my fingertips so I find myself fumbling around for the slide lock. An extended slide lock extends the unit just a bit further and enables be to more easily actuate the unit. I am runnng Deltac units but have also seen good reviews of units from Bastion, and NDZ. Note, you will need to supply the spring in every case I have seen.

Vickers Tactical Tactical Extended Magazine Release

One last part to cover – the magazine release. I can’t readily actuate the shorter OEM unit. I find I need just a bit longer release and really like the Vickers model that is made for them by Tango Down. Now, if you are wondering why, some units are so long that it is very easy for them to get bumped and release the mag. For some units, even laying the pistol down on it’s side might actuate the release. That may not matter for a competition pistol but I’d rather find a balance between ergonomics and reliability, hence my exclusive use of the Vickers model. Note, in most cases including the Vickers, you will need the spring. Here is a general listing of extended magazine releases:


So this wraps up a rather long post. I hope this helps you out.


If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



Glock Gen 3 Lower Parts Kits (LPKs) on eBay For Polymer80 Builds

In the last post, I gave you a general link to Glock parts and now we’ll start diving a bit deeper. When you are assembling a Polymer80 pistol, you will need a lower parts kit (LPK) that either you need to buy or will be part of a larger kit depending on what you are doing. If you are new to building, it is hard to go wrong with with an original equipment manufacture (OEM) Glock LPK vs. aftermarket that might have some challenges and others are best avoided. To avoid headaches while you learn, you want a Glock Gen 3 LPK. In the next post, I’ll go over the parts if you want to customize everything and you can do that but to start, go Glock.

What is in a LPK?

You will want to confirm the parts list with your seller, but here’s what would be in a full size Glock brand Gen 3 LPK:

  • Slide stop lever with spring
  • Slide lock & spring
  • Magazine release & spring
  • Trigger with trigger bar
  • Trigger housing with ejector
  • Trigger spring
  • Trigger pin
  • Trigger housing pin
  • Connector (5 pound)

LPKs are on eBay from Glock, Polymer80, marvel mystery parts (in other words, some have no maker identified and are to be avoided) and others. Again, for a newbie, I’d recommend starting with a Glock brand LPK to avoid potential stacked tolerance issues that you would need to address – if you are ready to drive in with all custom parts, you definitely can but it is still handy to have Glock OEM parts around for troubleshooting or spares just in case.

A few eBay buyer tips for you:

  • Look at the number of transactions and rating of the seller. If they have less than 10 sales, your potential risk increases.
  • Stick to Gen 3 parts. Glock has been evolving their pistols for a while now and the Polymer80 frames are designed with Gen 3 models in mind.
  • Make sure the parts you are looking for match the model you are building. Not all parts are interchangeable across models.
  • If the deal is almost too good to be true, it probably is. You’re not going to find a high-end assembled slide with barrel for $50. Sure there are used parts and good deals but there are also scams. This is another reason to look at the seller’s ratings.

OEM Glock LPKs Available on eBay

Here are some current posts on eBay – click on the banner and you can find even more:


Note, I have to buy all of my parts – nothing here was paid for by sponsors, etc. I do make a small amount if you click on an ad and buy something but that is it. You’re getting my real opinion on stuff.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.



Finding Parts For Your Polymer 80 Pistol Build on eBay

I really like building the Polymer80 pistols (Why Polymer80s Excite Me, Tips for Smooth Polymer80 Pistols, and Troubleshooting Your Build). What attracts me is the 1911-like grip angle, Picatinny Rail and the ability to customize the pistol however I want it. You will not save money doing these builds but the results are really cool. When you are planning a build, there are the expected sources of parts like 80P Builder and Glock Store but also a big one that might surprise you – eBay. I’m going to do a series of posts over the next few days with links to a variety of parts listed there.

A few tips for you:

  • Look at the number of transactions and rating of the seller. If they have less than 10 sales, your potential risk increases.
  • Stick to Gen 3 parts. Glock has been evolving their pistols for a while now and the Polymer80 frames are designed with Gen 3 models in mind.
  • Make sure the parts you are looking for match the model you are building. Not all parts are interchangeable across models.
  • If the deal is almost too good to be true, it probably is. You’re not going to find a high-end assembled slide with barrel for $50. Sure there are used parts and good deals but there are also scams. This is another reason to look at the seller’s ratings.

Polymer80 parts in general:

Click on a banner ad to see a given post plus many more will appear as well:


If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.