Pivot pin stuck

[pro2]

I have an lmt mrp piston upper on a sun devil lower. The fit between upper/lower is really tight, to the point where I have to use a plastic push pin tool and a hammer to get them out, especially the pivot pin. I installed an anti tilt buffer and need both pins out to pull the upper off the lower and now I can not get the pivot pin out. I have broken three plastic push tools trying to hammer the pin out. Any suggestions on what to do?

Thank you for your help.

[militarymoron]

are you trying to tap it out with the takedown pin in or out? try a drop of oil, and with the takedown pin in first.

[pro2]

Takedown pin is out. The buffer has an indexing nipple that protrudes into the bolt carrier and the upper won't come off unless I could somehow push the buffer back enough to pivot the upper. The pivot pin was coming out when I could pivot the gun, now not at all.

[Belmont31R]

Try the oil as mentioned, and give it some time to soak in.


Try a metal punch that is just small enough to fit in the hole, and place it flat against the pin. If you mar the pin a little cold blue on a q-tip will take care of it since the pin is steel.


Id buy a couple pivot pins as well and see if one of them isn't a better fit. They are mass produced, and will have different OD's. You might get one that is a couple thousands smaller, and be able to take the weapon apart without as much hassle in the future.

[Rated21R]

I had this problem with my MUR and lower. I took some Slip 2000 EWL, pulled the takedown pin completely out and hammered it through from both sides. A few times on each side and now everything fits like a glove and no issues.

[militarymoron]

put the takedown pin back in, then try the pivot pin with a drop of oil. then do the takedown pin.

[pro2]

Ok, I'll try that.

[Peanut]

Just a thought.

Try pulling or moving the upper receiver back anf forth while you push on the pivot pin.

With your set up, the action spring may be pushing the upper forward causing pressure on the pivot pin.

[pro2]

Ok, so I finally got time to go to the hardware store and get some steel punches. Back at the house I wrapped the gun in a shop rag, put it in a wise and dropped some kroil on the pins and waited. After the oil had worked for about ten minutes I tapped the pin out:dance3: It was almost like welded in there. I'm going to use a standard carbine buffer for now until the gun looses up some. Thanks again for the advice.

[cz7]

CRC freeze off is a great tool and cleans light foaling too please look into ...