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.

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