Any tricks on how to get a stuck detent out of the pin? I can't get the pin to come out of the receiver to allow me to remove the upper.

Thanks in advance.

Rear pin?  Take off the stock, remove the spring.





Front pivot pin?  A couple drops of CLP or Rem-oil on either end, wait, tap it out to the stop, and use the detent pin removal tool.  





Tool is Figure E-3,Pivot Pin Removal Tool,  on the last 20 pages of: ARMY TM 9-1005-319-23&P



Sorry if I missed something subtle.



 

I have no idea why they keep that tool listed in the manual.  Front pivot pins can be taken out by pulling the pin all the way out until it stops.  On the front of the pin there is a small hole, insert a small allen wrench (.050) or paperclip into it.  Depress the detent into the receiver and turn the wrench up or down.  Pull the pin out, but be prepared for the detent and spring to pop out.

Dammit.



Last time I used that tool was probably 6-7 years ago.   I swear I never saw/noticed that hole in the pivot pin and gave it the slightest thought.



Thanks, RLR, I appreciate the lesson as well.



My apologies to the OP for my less useful answer.



 

The front pivot detent pin must have a rough edge on it because simple pressure and even light tapping does not move the pin. I will try the oil method...I know that i can get it out if I can get the larger pin to the out position by using that hole on the pin.


I will let you know how it goes. If the oil method doesn't work I guess that I can try to slide something in that small space and retract the detent enough to get it to release the pin.

Thanks for the suggestions.

I had a selector detent that for some reason was rough enough in the right places that it wouldn't let me safe the weapon easily, so I think I understand.  It's probably  (
) either:



1. A  rough detent pin nose or shaft.  

2. A rough pivot pin along the shaft or in the hole the pin fits into.

3. Some crud or corrosion.



Can we assume you didn't slog it through some grit/mud and have #3 going on?  Maybe some aerosol like 'Kroil' in there to flush it?



Other than that, the tap-tap method with a delron pin seems to be my best suggestion.  A Delron pin is softer - in case it walks so you don't hit your lower with steel,.  And the area at the pivot seems stout enough to take a few careful whacks.



Other than that, I got nuthin'.  

Well,

I hit the pin with a center stamp a couple of times and actually managed to break the lodged detent in half. The tip of the broken detent was flat (i don't know if that was before the tapping or after) but I managed to get it free. I just replaced the entire mechanism with parts and seems to be fine.

Thanks for the suggestions but brute force was the winner!

Sounds like it was in backwards.



 

How can you tell if the detent pin is in backwards?

I am curious about this too....I inspected the next one that I placed for differences between sides and could not tell.  Educate me....

Everyonce in a while you will get one that is flat on one end.  It is unusual - probably a defect.  Poroper ones are round on both ends.

Of course the safety detent is different, however it won't, or shouldn't fit in the pivot pin's spring/detent tunnel, so it is almost impossible to mix them up.

Glad you got it worked out.

Good, now don't let it happen again.  




 

I wish I knew what I had done so I could prevent it again. I will definitely pay more attention to the ends of the detents next time.