[Ket19]

So I bought a Glock 19 gen 5 on line as a FBI trade in
Looked like new so I cleaned it up, swapped in a new Glock threaded barrel, a performance trigger, had the slide cut for the new Holosun enclosed optic and took it out shooting at my place to zero in the optic.
right off the bat I had failure to eject and stove piping every other round, after the optic was sighted in I went back inside and stripped the slide down , be sure to see the picture of what I found. Right off the bat I could not get the extractor plunger pin out, it basically was seized in the bore, once I pried it far enough away from the extractor i could get the firing pin block out and then remove the extractor.
I had to get a punch and beat the extractor plunger pin out of the slide, there was a piece of clear plastic in the bore that was jamming the extractor plunger pin, be sure to see pic, I have no idea how anything like that could possibly get in there but it did.
I polished the pin and checked the bore, replaced the extractor claw and I now have a excellent shooting Glock 19

 

[FrankenGunBuilder]

So I bought a Glock 19 gen 5 on line as a FBI trade in
Looked like new so I cleaned it up, swapped in a new Glock threaded barrel, a performance trigger, had the slide cut for the new Holosun enclosed optic and took it out shooting at my place to zero in the optic.
right off the bat I had failure to eject and stove piping every other round, after the optic was sighted in I went back inside and stripped the slide down , be sure to see the picture of what I found. Right off the bat I could not get the extractor plunger pin out, it basically was seized in the bore, once I pried it far enough away from the extractor i could get the firing pin block out and then remove the extractor.
I had to get a punch and beat the extractor plunger pin out of the slide, there was a piece of clear plastic in the bore that was jamming the extractor plunger pin, be sure to see pic, I have no idea how anything like that could possibly get in there but it did.
I polished the pin and checked the bore, replaced the extractor claw and I now have a excellent shooting Glock 19

That's what happens if you use too much Loctite on the screw that rides above the extractor depressor assembly. Ask me how I know.

 

[John_AZ]

Small dab of loctite on a proper length screw on the right side to secure the optic. Not going to get good extraction if your extractor can’t move around the case rim

 

[Ket19]

I can assure you that it was not loctite that caused this problem, this piece of plastic looked to be that of a water bottle. The slide had not been touched when I test fired the gun.

 

[FrankenGunBuilder]

I can assure you that it was not loctite that caused this problem, this piece of plastic looked to be that of a water bottle. The slide had not been touched when I test fired the gun.

Looks just like the substance in mine when the Loctite ran into the extractor depressor assembly but OK. It was in multiple. That's why I use Loctite gel on the screws now.

 

[Supersquatch]

Micro plastics.
They're everywhere.

 

[D20]

Looks just like the substance in mine when the Loctite ran into the extractor depressor assembly but OK. It was in multiple. That's why I use Loctite gel on the screws now.

Was yours clear? It would make sense that the pictured peice is hardened loctite, but how it's clear is what I'd like to know.

 

[FrankenGunBuilder]

Was yours clear? It would make sense that the pictured peice is hardened loctite, but how it's clear is what I'd like to know.

Yes, was opaque.

 

[fastbolt]

Interesting.

Firstly, I thought the FBI, like some other federal agencies, was required to destroy their firearms rather than selling/trading them.

Secondly, I'd wonder if that plastic piece ended up there due to improper cleaning practices by the former owner, by trying to force a plastic 'tool' into the channel which had a piece (tip) snap off.

Glad you figured it out.

 

[FrankenGunBuilder]

Interesting.

Firstly, I thought the FBI, like some other federal agencies, was required to destroy their firearms rather than selling/trading them.

Secondly, I'd wonder if that plastic piece ended up there due to improper cleaning practices by the former owner, by trying to force a plastic 'tool' into the channel which had a piece (tip) snap off.

Glad you figured it out.

No, it's too much Loctite. I've spoken to it before on this site.

Loctite is a polymer that cures in an anerobic environment. It cures back into a polymer and the green tinge is, hint, from the Loctite.

 

[Ket19]

Looks just like the substance in mine when the Loctite ran into the extractor depressor assembly but OK. It was in multiple. That's why I use Loctite gel on the screws now.

I respect what you are saying, what I’m telling you is is that the gun was not a mos, there were no screw holes to put loctite in, the slide got cut after the repair was made, I cut the slide myself and have used loctite most of my adult life, that piece of plastic was in there long before I got the gun, take from that what you want

 

[JohnnyReb]

I respect what you are saying, what I’m telling you is is that the gun was not a mos, there were no screw holes to put loctite in, the slide got cut after the repair was made, I cut the slide myself and have used loctite most of my adult life, that piece of plastic was in there long before I got the gun, take from that what you want

So you bought a 19M that was not MOS, and you cut the slide on that 19M without dissembling the slide first? Did you leave it bare metal?

 

[L-2]

Summary,
OP bought a used Glock; experienced malfunctions; upon a detail strip of the slide some type of solidified polymer or adhesive/thread-locker was found and cleaned out.

There's a bit of "noise" in Post 1 and later which is likely irrelevant, such as:

"FBI" info. Yes, an actual Bureau-owned gun would not be resold under current Federal rules/policies/regs. It's my understanding FBI Agents have some latitude in personally purchasing handguns which can then be approved for work use. It's possible the Agent or former Agent could then sell his/her personally-owned G19gen5. Whether the seller was actually a present or former FBI Agent is irrelevant.

The way the OP wrote Post 1, it made it seem as if the optic was made by someone other than the OP as the OP said he "had" the optic cut, but later in the thread the OP stated he'd cut the optic personally. The slide cut is likely irrelevant whether the OP had the slide cut by someone else or the OP doing it personally.

The wording in Post 1 also made it seem as if the slide was cut; a Holosun optic installed; and then during test fire malfunctions occurred. Then after all that, the solidified polymer/adhesive was then found upon a detail strip. Later in the thread, the OP stated the malfunction and cure was located prior to the slide cutting and optic install. These details are irrelevant, if not misleading; as it'd be a common installation error to allow too much thread-locker to be applied allowing the thread-locker to enter the extractor-depressor-plunger tunnel, preventing functioning of the extractor.

Loctite or Other Material.
The thread's posters apparently disagree as to what the solidified material is/was, whether Loctite-brand or other (thread-locker/adhesive). There are so many products on the market, although the OP's photo seems to show something liquid was poured into the Glock, then solidified causing the OP's malfunctions. How or why the unknown material was applied/inserted is open to speculation. I'm glad the material was located, fairly-easily removed; and the Glock is now functioning.

 

[Ket19]

No, it's too much Loctite. I've spoken to it before on this site.

Loctite is a polymer that cures in an anerobic environment. It cures back into a polymer and the green tinge is, hint, from the Loctite.

So I posed my photo and the same question to ai, now it may not be correct all the time, but neither is anyone else.


Thanks for the image — and yes, I’ve had a good close look.





🔍 Analysis:

• The piece is semi-clear, glossy, and flexible-looking, not brittle or chalky.
• It resembles polyethylene or PET plastic, commonly used in:
  • Water bottles
  • Plastic packaging
  • Clear cleaning patch wraps
• 
  
• There are black specks or carbon fouling embedded in it — consistent with exposure to gunpowder residue or heat.
• The shape and curl suggest it was sheared or pinched, not formed in place — not cured adhesive behavior.

✅ Conclusion:





This is not Loctite.

It is:

• Clear, which blue Loctite is not.
• Flexible or crumpled, unlike hardened Loctite which becomes rigid.
• Likely a foreign plastic fragment — most likely something that got introduced during cleaning, transport, storage, or packaging.

If it was found in the extractor plunger channel, this could have seriously interfered with reliable extraction. Clearing it out was the right move.



Let me know if you want help inspecting other parts to make sure nothing else is lodged or fouling the function.

 

[noreply]

If you look really close, you can barely make out "Aquafina" in the curvature from bottom to top.

 

[FrankenGunBuilder]

So I posed my photo and the same question to ai, now it may not be correct all the time, but neither is anyone else.


Thanks for the image — and yes, I’ve had a good close look.





🔍 Analysis:

• The piece is semi-clear, glossy, and flexible-looking, not brittle or chalky.
• It resembles polyethylene or PET plastic, commonly used in:
  • Water bottles
  • Plastic packaging
  • Clear cleaning patch wraps
• 
  
• There are black specks or carbon fouling embedded in it — consistent with exposure to gunpowder residue or heat.
• The shape and curl suggest it was sheared or pinched, not formed in place — not cured adhesive behavior.

✅ Conclusion:





This is not Loctite.

It is:

• Clear, which blue Loctite is not.
• Flexible or crumpled, unlike hardened Loctite which becomes rigid.
• Likely a foreign plastic fragment — most likely something that got introduced during cleaning, transport, storage, or packaging.

If it was found in the extractor plunger channel, this could have seriously interfered with reliable extraction. Clearing it out was the right move.



Let me know if you want help inspecting other parts to make sure nothing else is lodged or fouling the function.

Had I not done this to many of my own weapons I would not question. The situation is clearly stated in your post. You said you had the slide milled. They strip slides before being milled. You installed an optic. You used Loctite, I’m guessing 620, it ran into the extractor depressor assembly and hardened. Loctite is a polymer and forms a plastic like substance when it drys just like the picture in your post. The hardened Loctite, ok polymer, you used has a green tint and was not a clear color. I’ve had the blue Loctite dry clear and I use the blue Loctite gel stick going forward as, again, I’ve seen this dozens of times. It has been documented on this forum many times and I have also spoken to it not long ago. The situation is extremely common and happens to the best of us. We literally hear about a similar situation almost weekly or so it seems.

The extractor depressor assembly will stick and cause a variety of issues. Depending on the amount that flows in and the time it sits it can be extremely difficult to remove. I had one that took me hours and lots of different solvents to remove and I still had to hammer it out as nothing would make it budge other than force. I did not want to use heat as it would ruin the slide finish. It does not take much Loctite to make a complete mess of the extractor depressor assembly. I too have years of experience but I also make mistakes and that’s the knowledge being shared here. Sure wish I was perfect but I’m far from it.

 

[FrankenGunBuilder]

If you look really close, you can barely make out "Aquafina" in the curvature from bottom to top.

Man, I don’t see that. Looks more like it says Dasani to me. 🤷‍

 

[Ket19]

Summary,
OP bought a used Glock; experienced malfunctions; upon a detail strip of the slide some type of solidified polymer or adhesive/thread-locker was found and cleaned out.

There's a bit of "noise" in Post 1 and later which is likely irrelevant, such as:

"FBI" info. Yes, an actual Bureau-owned gun would not be resold under current Federal rules/policies/regs. It's my understanding FBI Agents have some latitude in personally purchasing handguns which can then be approved for work use. It's possible the Agent or former Agent could then sell his/her personally-owned G19gen5. Whether the seller was actually a present or former FBI Agent is irrelevant.

The way the OP wrote Post 1, it made it seem as if the optic was made by someone other than the OP as the OP said he "had" the optic cut, but later in the thread the OP stated he'd cut the optic personally. The slide cut is likely irrelevant whether the OP had the slide cut by someone else or the OP doing it personally.

The wording in Post 1 also made it seem as if the slide was cut; a Holosun optic installed; and then during test fire malfunctions occurred. Then after all that, the solidified polymer/adhesive was then found upon a detail strip. Later in the thread, the OP stated the malfunction and cure was located prior to the slide cutting and optic install. These details are irrelevant, if not misleading; as it'd be a common installation error to allow too much thread-locker to be applied allowing the thread-locker to enter the extractor-depressor-plunger tunnel, preventing functioning of the extractor.

Loctite or Other Material.
The thread's posters apparently disagree as to what the solidified material is/was, whether Loctite-brand or other (thread-locker/adhesive). There are so many products on the market, although the OP's photo seems to show something liquid was poured into the Glock, then solidified causing the OP's malfunctions. How or why the unknown material was applied/inserted is open to speculation. I'm glad the material was located, fairly-easily removed; and the Glock is now functioning.

First off, Blackstone shooting is where I got the firearm from and they were the ones that called it a bureau trade-in,
Secondly, when I picked up the firearm from my FFL, I brought it home, loaded one magazine and shot the gun on my property approximately 15 rounds half of which stove piped, the gun is not an MOS, nor at that point had it ever had Loctite poured into it, that’s just a fact you’re all gonna have to deal with. Yes, I chucked the slide up on a mill and cut it for the optic drilled and tap the slide. I am a business owner of a trucking company. I do machine work. All of my work is done in house repairs everything I have used Loctite since the day it came out. You must assume that everybody that uses loctite don’t know what they are doing, when I assembled the plate on the slide, I used one drop of blue Loctite per screw, that also is another fact. From the moment I picked up the gun at my FFL took it home shot it then went in machine the slide we’re all done within several hours of each other. I apologize for the sequence where it got confusing, but I’ll let the fact speak for themselves., the forensic science behind every move that I have made is really not the issue and in my experience with blue Loctite, it never dries to a clear form as in that picture, and to think that someone would think I would pour Loctite in the gun like that is ridiculous

 

[John_AZ]

Cool. You figured out your problem.

The fact that someone would think you’d pour loctite into your firearm is not ridiculous. Spend some time here. You’ll see it more than once. And far more ridiculous things.

 

[Ket19]

Man, I don’t see that. Looks more like it says Dasani to me. 🤷‍

I used 242 or 243 can’t remember without running to the shop to look at the bottle but it was blue. I used 1 drop per screw,
On a side note I shoot bowling pins every Tuesday, with my Glock 20 I was a consistent 4 th or 5th place shooter for the past year. Magical as it may seem, last Tuesday with this new gun loaded with buffalo bore outdoorsman ammo went there and shot the very 1st perfect score. That’s 15 of 15 off the table to go home a winner. Thank for all participation, the attention to loctite usage is well noted, a lesson I learned many years ago ! Thanks