Glock 21 in 45acp Theme Build

bkbrno said:
You don't have to modify the frame but a trigger housing will not seat all the way down if you don't modify something. There is a ridge molded into the frame that keeps the trigger housing from going all the way into the slot. It is well known. Lone Wolf made a part to compensate for it, the Universal Trigger Housing. MGB made a video to describe the problem and his solution when using an OEM Glock housing. I thought I posted pictures but all I can find is my post here describing what I did. Product Review - PF45 Build Day With My Brother I'll keep looking.

With nothing done to correct this, the pin for the trigger housing will not go in easily or at all. The trigger housing will be slightly too high and cause the slide to bind. It will also put the striker higher than it should be and give you minimal sear engagement.

My frame and two others I saw had this issue. Enough people had this issue that MGB did a video on it. I'm not sure how you escaped it.
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FrankenGlock said:
Not discounting what you are saying but I’ve never experienced that issue with any of my PF45 builds. Maybe I found another way to overcome the issue but don’t remember there being any.
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RE: Testing the fit of a PF45 frame with an OEM 5406 Trigger Housing:

Apologies for the long post in advance, but I decided to test out an unmodified Glock 5406 trigger housing and figured some folks may be inquisitive about why it appears to install in my frame with no issues.

I have a prepared and drilled PF45 frame with all OEM parts that has never been built. Stock P80 Front Locking Block and Rear Rails that go in perfectly with pin holes drilled slightly smaller than specifications to keep the pins snug and tidy. You can push the pins out with a punch with your hand with a tad of effort. Just about right in my mind as I hate loose pins.

So, for grins, I just tried insertng a virgin, unmodified 5406 trigger housing in the frame to see how it will fit. I pushed the trigger bar inside the frame and rear rail and it rode a smidgen higher than being flush with the frame. The rear tab of the trigger housing was a micro amount higher than the frame. Just a bit. I didn't measure it, but it was 1/32 or 1/16 of inch higher, or perhaps less. Just a tad of light showing through. I did not try to force it in any more and lived with the normal pressure that someone would use building the frame. Everything looked clear by eyeball peering through the drilled hole and it looked lined up, so I tried to insert the rear pin. There was a bit more friction inserting the pin when compared to inserting it with just the rear rail installed with no trigger housing. It needed a tap or two to go in, but it certainly was nothing major. It was rather minor indeed. However, the trigger housing did appear to lower into the frame more once the pin was inserted fully. I inspected the rear tab of the trigger housing where it touches the frame and there was no light at all now. It is flush. I looked to see if the ejector was doing a wheelie and lifting in the front of the trigger housing slightly and it doesn't appear to do that. It looks flush and level throughout.

This build has been sitting for awhile now so this has been the first time I have tried inserting the trigger housing. I have everything but a handful of inner parts, the slide and the barrel and hope to complete it sometime soon once life quits hitting me with hurdles.

Having just tested this out, I would like to give some input and $00.02 here about why some folks may have to grind their trigger housing to fit in the frame. It's my theory based on how I prepared the frame. When I drilled this frame I did it in a batch of frames in one go (Not everyone's cup of tea due to the risk). I setup everything very precisely with all the frames, sealed the jigs with tape tightly, check the press to make it sure it was square and level, checked runout on drill bits, ensured the bits were 90 degrees to the frame, tight in the collet, and drilled every one of the frames sequentially with about the same amount of drill pressure and friction. It is easy to have consistent pressure drilling when you build multiple frames Henry Ford style like an assembly line. All drill procedures were in sequential order for each frame and I drilled all of them in a matter of minutes. The end result is that each one of the frames and builds with different models ALL had the same approximate amount of sear engagement at about 90% or greater. The holes appear to be perfectly drilled on all the frames and very consistent, or as close to it as you can get by doing this by hand.

When I did this drill procedure assembling line style, the first frame I checked for correctness was the PF45 frame. This is because the frames were scarce and if I fucked up, I wanted to reorder one while they were still available. It was done during the parts drought. I was predicting I would need to massage the arch of the rear rails on the PF45, but the rear pin inserted with no sweat and the rear rail looked flush and aligned. I was really pleased. This told me I had lined everything up on the drill press correctly.

So with this lengthy background info, I have a theory that the PF45 frame needs it's holes drilled almost perfectly to have the rear 5406 trigger housing work without having to dremel the side of the trigger housing down like illustrated in MGB's video. Or, perhaps there are slight variances in the 5406 parts? Based on me assessing the amount of limited force I had pushing the pin in (not much at all), I could see there being a slight issue if your pin holes were just a tad off when you drilled them, or perhaps modifying the arch of a P80 rear rail could do it. The pin holes and alignment of P80 rear rails and having to modify the arch is a known issue. I do not have a set of Rook Rails for this thing to test them out too.

However, my test today, right now, shows that a 5406 housing appears to fit fine and sits flush using P80 rails. Granted I don't have a slide to fully test how this frame will rack when it's built, but for now, I am not messing with the 5406 housing and will cross that bridge when I buy a slide and barrel for this thing.

I don't have the time right now to post a photo, but I may do it tonight.

Sorry for the long winded post, but I wanted to test this out and I'm certain there are other questions others may have about this too.

Cheers!
 
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USApat, need some more detail. I'm not following you. Just kidding, awesome post. When I do mine, I use a drill press with the housing closed tightly and duct taped on three sides so it does not move. It may explain why I don't have any issues with things fitting as they should. Seems that it mirrors what you see in your builds. As the Mandalorian would say, "this is the way."
 
FrankenGlock said:
USApat, need some more detail. I'm not following you. Just kidding, awesome post. When I do mine, I use a drill press with the housing closed tightly and duct taped on three sides so it does not move. It may explain why I don't have any issues with things fitting as they should. Seems that it mirrors what you see in your builds. As the Mandalorian would say, "this is the way."
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Hold the phone! I now see the issue. I will update my post quickly and leave my post intact above.
 
USApat said:
RE: Testing the fit of a PF45 frame with an OEM 5406 Trigger Housing:

Apologies for the long post in advance, but I decided to test out an unmodified Glock 5406 trigger housing and figured some folks may be inquisitive about why it appears to install in my frame with no issues.

I have a prepared and drilled PF45 frame with all OEM parts that has never been built. Stock P80 Front Locking Block and Rear Rails that go in perfectly with pin holes drilled slightly smaller than specifications to keep the pins snug and tidy. You can push the pins out with a punch with your hand with a tad of effort. Just about right in my mind as I hate loose pins.

So, for grins, I just tried insertng a virgin, unmodified 5406 trigger housing in the frame to see how it will fit. I pushed the trigger bar inside the frame and rear rail and it rode a smidgen higher than being flush with the frame. The rear tab of the trigger housing was a micro amount higher than the frame. Just a bit. I didn't measure it, but it was 1/32 or 1/16 of inch higher, or perhaps less. Just a tad of light showing through. I did not try to force it in any more and lived with the normal pressure that someone would use building the frame. Everything looked clear by eyeball peering through the drilled hole and it looked lined up, so I tried to insert the rear pin. There was a bit more friction inserting the pin when compared to inserting it with just the rear rail installed with no trigger housing. It needed a tap or two to go in, but it certainly was nothing major. It was rather minor indeed. However, the trigger housing did appear to lower into the frame more once the pin was inserted fully. I inspected the rear tab of the trigger housing where it touches the frame and there was no light at all now. It is flush. I looked to see if the ejector was doing a wheelie and lifting in the front of the trigger housing slightly and it doesn't appear to do that. It looks flush and level throughout.

This build has been sitting for awhile now so this has been the first time I have tried inserting the trigger housing. I have everything but a handful of inner parts, the slide and the barrel and hope to complete it sometime soon once life quits hitting me with hurdles.

Having just tested this out, I would like to give some input and $00.02 here about why some folks may have to grind their trigger housing to fit in the frame. It's my theory based on how I prepared the frame. When I drilled this frame I did it in a batch of frames in one go (Not everyone's cup of tea due to the risk). I setup everything very precisely with all the frames, sealed the jigs with tape tightly, check the press to make it sure it was square and level, checked runout on drill bits, ensured the bits were 90 degrees to the frame, tight in the collet, and drilled every one of the frames sequentially with about the same amount of drill pressure and friction. It is easy to have consistent pressure drilling when you build multiple frames Henry Ford style like an assembly line. All drill procedures were in sequential order for each frame and I drilled all of them in a matter of minutes. The end result is that each one of the frames and builds with different models ALL had the same approximate amount of sear engagement at about 90% or greater. The holes appear to be perfectly drilled on all the frames and very consistent, or as close to it as you can get by doing this by hand.

When I did this drill procedure assembling line style, the first frame I checked for correctness was the PF45 frame. This is because the frames were scarce and if I fucked up, I wanted to reorder one while they were still available. It was done during the parts drought. I was predicting I would need to massage the arch of the rear rails on the PF45, but the rear pin inserted with no sweat and the rear rail looked flush and aligned. I was really pleased. This told me I had lined everything up on the drill press correctly.

So with this lengthy background info, I have a theory that the PF45 frame needs it's holes drilled almost perfectly to have the rear 5406 trigger housing work without having to dremel the side of the trigger housing down like illustrated in MGB's video. Or, perhaps there are slight variances in the 5406 parts? Based on me assessing the amount of limited force I had pushing the pin in (not much at all), I could see there being a slight issue if your pin holes were just a tad off when you drilled them, or perhaps modifying the arch of a P80 rear rail could do it. The pin holes and alignment of P80 rear rails and having to modify the arch is a known issue. I do not have a set of Rook Rails for this thing to test them out too.

However, my test today, right now, shows that a 5406 housing appears to fit fine and sits flush using P80 rails. Granted I don't have a slide to fully test how this frame will rack when it's built, but for now, I am not messing with the 5406 housing and will cross that bridge when I buy a slide and barrel for this thing.

I don't have the time right now to post a photo right now, but I may do it tonight when I get more time. My phone doesn't connect with the tower where I am now, and I have to slave my phone to the computer or send it over with Blue Tooth and I'm busy right now.

Sorry for the long winded post, but I wanted to test this out and I'm certain there are other questions others may have about this too.

Cheers!
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I have a big edit to my post above which I will leave intact. 👆

I have inspected the trigger housing further and there is an issue with it! Whether it affects the operation of the gun I don't know because I lack the barrel and slide!

I checked the trigger housing to see if it was level, but I didn't look down on the frame in a bird's eye view!
If you peer down from the top you can see the trigger housing has shifted sideways rather than up and down. The rear portion of the trigger housing is cocked to the right due to the ridge that is inside the frame pushing it outward, with the northward end with the ejector sitting in place but at an angle now too, but flush against the rear rail/frame. I will try and get some pictures later.
 
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bkbrno said:
For the PF45 and PF45 only.

The instructions specify a Gen3 G20 SF trigger housing. Period, dot. The slot in the rear of the frame is moulded for the SF housing. Not really building up around a trigger. More of getting the correct parts from the start because the G20/21 has two available parts depending on whether G21 or G21SF. I bought the wrong trigger housing once and it stopped my build for two weeks while I waited on parts.

Now, hang on here, the G21 SF trigger housing has the same exterior dimensions as a Gen5 housing but the internal parts are Gen3. It has a pointy end instead of squared off like the Gen3.

The Gen5 trigger housing is the the same external shape as the Gen3 SF housing but the internal mechanism is all different. The Gen5 trigger bar is different as well as the trigger shoe. The shoe is different because it is set up for the ambi slide release. I have not had a problem with the extra space left for the ambi release but it doesn't mean you won't. I did not change the shoe but some people have.

Keep it simple. Buy a Glock OEM Gen3 SF trigger housing and a Gen3 trigger. I don't know of an aftermarket alternative. Lone Wolf had a universal trigger housing specific to the PF45 at one time but I don't think they are available currently. Haven't looked in the last year.

Or, as a slight upgrade, buy a Gen5 Trigger Housing, Gen5 trigger, and Gen5 slide back plate. 3 parts.

If you have done dozens of these, I suppose you could cut and modify a Gen3 trigger bar. I have not done that before so no comment. With no parts to compare and match, I would not go this route for the first try. You will have to buy both Gens if you want to have a template to work from.

One last note. The trigger housing on the PF45 needs to be modified to drop all the way down to the frame. I suggest the available MGB video to describe this modification. While it is almost always a good idea to modify the cheapest part, I couldn't live with the error in the PF45 frame casting that requires this modification. I posted a fix on here. It takes about 10 seconds with a dremel sanding drum and allows you to drop in a trigger housing without modification. I don't know what happens when you grind off the back section of a Gen5 housing per MGB's video, it is uncharted territory for me. Because I modified my frame, the Gen5 part dropped right in on my PF45. I keep specifying PF45 because it is the only P80 frame that you have to do this to.

Sorry I don't have part numbers for you, I can't find my notes. It's pretty clear if you order from Midwayusa.
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First off. I can and will get a G20/21 SF frame. .
Second this build is the second of four Large Frame Glocks. Next two will be a G40 then a G41.
Ok , I have a G20 with a Lone Wolf slide and barrel . I have 2 G20/21 frames , one is a complete frame ready for a G40 slide. The second is this build, just need a Cerakote pin kit , slide , barrel and slide plate. All other parts have been ordered .
My plan is to get a SF frame and do this FrankenGlock trigger when I get the parts for it and swap slides to the SF frame.
One concern is the firing pin safety contacting the trigger arm at a different position if I use a gen 5 trigger and a gen 5 trigger housing. I think that will work better than the 3 to 5 FnG trigger with cutting the spring hole on the arm.
 
The problem I described was significant enough for a manufacturer of parts to make a special part for this particular model. Enough people had trouble that MGB did a 45 minute video on how to correct it.

It is entirely possible to push-cram-shove-pound the trigger housing into place. Or you could make the mod and you trigger housing will drop right in just like every OEM Glock, P80 (every other model), SCT, Dagger, Geisler, et al. I chose drop in fit and avoided grinding most of the ejector off because it sits too high. I avoided having to tweek the sear engagement because the slide wasn't in the right place.

I came up with a different way and it modifies the most expensive part instead of the cheapest part. I was comfortable doing this, you may not be. I can fit any trigger housing right out of the package. Modifying the cheapest part will require you to modify every replacement part in the future.

I could squeeze my housing down enough to close the gap but it would have a lot of tension on the pin. Plastic under that much pressure is, well, plastic. It will not stay that way but migrate out of position over time.
 
MikedaddyH said:
First off. I can and will get a G20/21 SF frame. .
Second this build is the second of four Large Frame Glocks. Next two will be a G40 then a G41.
Ok , I have a G20 with a Lone Wolf slide and barrel . I have 2 G20/21 frames , one is a complete frame ready for a G40 slide. The second is this build, just need a Cerakote pin kit , slide , barrel and slide plate. All other parts have been ordered .
My plan is to get a SF frame and do this FrankenGlock trigger when I get the parts for it and swap slides to the SF frame.
One concern is the firing pin safety contacting the trigger arm at a different position if I use a gen 5 trigger and a gen 5 trigger housing. I think that will work better than the 3 to 5 FnG trigger with cutting the spring hole on the arm.
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I didn't use any fancy measuring equipment but I did check where the firing pin safety started to touch on both as I pulled the slide back, looking through the mag well. I'm sure it is not the same place if you get down to thousandths of inches but I couldn't get it to do anything it wasn't supposed to do. By eyeball it seemed to engage about the same place. Yet another reason to have both generations on hand.
 
Bongo Lewi said:
I also have the XD/M in 10mm. I think it's the best polymer striker in that caliber. I also have a G20 which is fine, but I like the SA better. The XD design is starting to look a little long in the tooth, but you can't beat its reliability. Both the Glock and The Springfield eat any 10mm ammo I feed them.

Take a look at the Echelon if you havent already. Springfield is on a roll.
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I also have an EAA Witness P Carry in 10mm, it's like a Ferrari. Picky eater... If it's too hot it will not cycle . It's got a 23lb recoil spring and will throw brass 30 feet ! I can bang steel at 100 yards no problem with that beast.
 
MikedaddyH said:
I also have an EAA Witness P Carry in 10mm, it's like a Ferrari. Picky eater... If it's too hot it will not cycle . It's got a 23lb recoil spring and will throw brass 30 feet ! I can bang steel at 100 yards no problem with that beast.
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I run 22 to 24 lb RSA's in my G20L/40 clones. Really helps in the motivation and feeding of the long 10MM slides.
 
I can get a couple extra trigger housings , I have extras for G17 s gen 3 & 4 now. Will order a gen 5 trigger housing for a SF frame and a GPT setup as well.
 
FrankenGlock said:
bkbrno, have you tried the Gen 5 trigger housing yet?
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Yes, I did a PF45 and a 940C. No issues with the PF45 because I modified the frame. I did it as soon as the Gen5 G20 trigger bar became available a few months ago.
 
I believe the Gen 5 trigger fits all Glocks except the 43/48 so no SF version needed. You have to modify the legs a bit on the older frames, but they work great there too. I absolutely hated the Glock Gen 4 and older triggers with a passion. Was like someone threw wet sand in the mechanism and left it that way. Can't say it enough what an improvement the Gen 5 standard housing and or GPT does to the feel/function of the gun.
 
I've helped a few over there with the mods. Helped CCIman with his conversion. It's funny as the long timers on that board almost don't like to advertise when they do Frankenmods.
 
Purest !
They don't like changing.
Most answers are...No it's doesn't fix . Or Only use OEM Glock parts. Before even thinking. I never respond to those comments. Been lurking on that site for a decade and a half, 4 different Handles.
 
MikedaddyH said:
Purest !
They don't like changing.
Most answers are...No it's doesn't fix . Or Only use OEM Glock parts. Before even thinking. I never respond to those comments. Been lurking on that site for a decade and a half, 4 different Handles.
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Isn't that the truth. Don't need those doo dads for shootin. Gonna stick with my plastic sights. Trigger mods don't do nothin for ya and red dots are for girls. I like my trigger pull like I like my compound bows, long, hard, and rough. I think they were talking about Glock triggers. Anyway, yeah, heard it all.
 
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I put a couple pf45s together.
One with g20 lone wolf slide and extended barrel in 10mm and have a 9x25 dillon barrel to go with it.
Another was in 45aarp which I haven't tried yet.
I can't remember whoes parts I used.

Biggest issue I have found is non oem Glock parts when building any of my 80% jobbies.

See a few are want to talk 10mm.
Well I have the Sig xten, XDME, Tanfoglio stock3 (Also 9x25 Dillon), S&W M&P, Dan Wesson Razor back, Kimber, P40L, this pf45 style build and it's likely I ain't remembering one other or more. Ohh see, bought a girsan 6" long slide double stack.
I recommend not getting the EAA Witness Girsan and waiting on the guns SDS imports are supposed to be bringing in. TISAS /MAC
I load real 10mm 180gr at 1325-50 depending on gun same load.
Should purchase a 10mm revolver but if I did, it would be impossible not to ream it for 10mm Magnum.
 

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