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Posted: 5/28/2021 10:19:50 PM EDT

Please tell me somebody know what’s going on. I don’t know if the fcg area is too tight due to not enough material removed, cmmg lpk and I polished the parts and I polished the inner walls. The safety won’t move at all and it does the same thing with the stock off and pistol grip. Anybody?Video

Posted: 5/28/2021 11:35:55 PM EDT

[#1]

Have you used a caliper to measure the various FCG pocket dimensions? Kinda need this information to help you move forward. Gotta ask but did you carve that out with a hammer and chisel?

Posted: 5/28/2021 11:53:53 PM EDT

[#2]

First off....I'd find that angry beaver that has been gnawing on your 80 percent and end it.

Attached File

Clean up the FCG pocket, measure and confirm dimensions.

Confirm location of hammer/trigger pin holes. It may be the angle/s in your vid but the trigger pin looks to be high in the hole, and hammer pin low in it's hole

Attached File

Posted: 5/29/2021 12:00:30 AM EDT

[#3]

Quoted:
Please tell me somebody know what’s going on. I don’t know if the fcg area is too tight due to not enough material removed, cmmg lpk and I polished the parts and I polished the inner walls. The safety won’t move at all and it does the same thing with the stock off and pistol grip. Anybody?Video

View Quote

Posted: 5/29/2021 12:02:27 AM EDT

[#4]

Egads , an .

Posted: 5/29/2021 12:07:38 AM EDT

[#5]

Is the trigger guard in backwards too?

Posted: 5/29/2021 12:12:07 AM EDT

[#6]

Holy cow...

Time for a new lower.

Posted: 5/29/2021 12:43:57 AM EDT

[#7]

I think a small thermonuclear device will clean that up.

Posted: 5/29/2021 9:59:06 AM EDT

[#8]

I drill pressed it with plunge cutting and sanding it with files cause my cross slide vise will not lock into the press base. The pins began to almost start walking to due to me taking them in and out trying to fix it. I’ve milled 3 successful before but neither was forged. I was thinking will a drop in with anti walk pins resolve all of this?

Posted: 5/29/2021 2:19:19 PM EDT

[#9]

I'd just resolve it with a new lower, personally.

Posted: 5/29/2021 3:42:27 PM EDT

[#10]

Cut it up or smash it up.

Try again.

Posted: 5/29/2021 3:53:42 PM EDT

[#11]

Quote History

Quoted:
First off....I'd find that angry beaver that has been gnawing on your 80 percent and end it.

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224005_Photos_jpg-1959091.JPG

Clean up the FCG pocket, measure and confirm dimensions.

Confirm location of hammer/trigger pin holes. It may be the angle/s in your vid but the trigger pin looks to be high in the hole, and hammer pin low in it's hole

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224748_Photos_jpg-1959088.JPG

View Quote

Holy Hannah!

Not today Mr. ATF...not today.

Posted: 5/29/2021 4:22:50 PM EDT

[#12]

do you have a band saw?

Posted: 5/29/2021 4:25:39 PM EDT

[#13]

Posted: 5/29/2021 4:27:15 PM EDT

[#14]

Quote History

Quoted:
First off....I'd find that angry beaver that has been gnawing on your 80 percent and end it.

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224005_Photos_jpg-1959091.JPG

Clean up the FCG pocket, measure and confirm dimensions.

Confirm location of hammer/trigger pin holes. It may be the angle/s in your vid but the trigger pin looks to be high in the hole, and hammer pin low in it's hole

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224748_Photos_jpg-1959088.JPG

View Quote

Holes also appear to be egged out!

Posted: 5/29/2021 5:28:11 PM EDT

[#15]

Quote History

Quoted:

Holes also appear to be egged out!

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
First off....I'd find that angry beaver that has been gnawing on your 80 percent and end it.

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224005_Photos_jpg-1959091.JPG

Clean up the FCG pocket, measure and confirm dimensions.

Confirm location of hammer/trigger pin holes. It may be the angle/s in your vid but the trigger pin looks to be high in the hole, and hammer pin low in it's hole

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224748_Photos_jpg-1959088.JPG

Holes also appear to be egged out!

Agreed.

Posted: 5/29/2021 6:19:49 PM EDT

[#16]

Picture makes the hammer look like the one hole is higher than the other and the holes on an angle out of alignment too.

Posted: 5/29/2021 6:25:34 PM EDT

[#17]

Quote History

Quoted:
Picture makes the hammer look like the one hole is higher than the other and the holes on an angle out of alignment too.

View Quote

True.

Hammer may be binding on pin.

Almost looks as if the hammer at pivot point may be contacting the front of FCG pocket?

Again, I'd clean things up/confirm dimensions before anything else.

Posted: 5/29/2021 9:39:07 PM EDT

[#18]

I thought this was a fake post at first.

This thread should be pinned.

Posted: 5/29/2021 10:22:30 PM EDT

[#19]

It’s worth what it weighs at this point. Throw that thing away.

Posted: 5/29/2021 10:54:11 PM EDT

[#20]

Quote History

Quoted:
First off....I'd find that angry beaver that has been gnawing on your 80 percent and end it.

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224005_Photos_jpg-1959091.JPG

Clean up the FCG pocket, measure and confirm dimensions.

Confirm location of hammer/trigger pin holes. It may be the angle/s in your vid but the trigger pin looks to be high in the hole, and hammer pin low in it's hole

https://www.ar15.com/media/mediaFiles/416992/Screenshot_20210528-224748_Photos_jpg-1959088.JPG

View Quote

Posted: 5/29/2021 11:58:21 PM EDT

[#21]

is there a lake or river nearby?

Posted: 5/30/2021 12:59:59 AM EDT

[#22]

Yikes!

Posted: 5/30/2021 9:14:07 AM EDT

[#23]

#1 rule, don't let Darwin be your friend.

--> Dremel, and a $20 caliper from HF.

Posted: 5/31/2021 6:08:17 PM EDT

[#24]

Quote History

Quoted:
I've milled 3 successful before but neither was forged. I was thinking will a drop in with anti walk pins resolve all of this?

View Quote

Probably a bad forging.

Posted: 5/31/2021 6:35:05 PM EDT

[#25]

WOW!!!

Posted: 5/31/2021 6:36:13 PM EDT

[#26]

No offence, but did you mill that with a hammer and chisel?

Get a new lower,5D jig and try again.

Posted: 5/31/2021 7:14:22 PM EDT

[#27]

?? This...

Hate to say it but that lower is fucked. Pin holes look out of alignment. Once the material is gone no real good way to correct it....

Use a jig on the next one.

Posted: 6/16/2021 8:04:52 PM EDT

[#28]

Have you pulled the safety detent and spring all the way out and see if the lever/shaft will rotate with that removed? I ran across a setup where the hole for the safety shaft detent didn't like the detent pin, I think I remember it was too pointed and would not let it rock up out of the detent from safe to fire position once it had pressure from the FCG springs on the system.
Kinda scared me cause the lower worked fine with a different lower kit. My daughter wanted to build one so I stripped it down and gave her all new parts and guess tolerances just were not right. Massaged the detent pin end and the detent hole on the safety shaft, now smooth as butter but still locks up firm at the stops.
Can't really speak to the pin holes being round, might be lube or shadows in the picture or they could be egged out but didn't look like the FCG was crossed up in the pocket putting stress on the safety, at least to my old eyes.
Good luck with troubleshooting.