ar15 takedown pin

[calixt0]

I was hoping to replace my rear takedown pin on my ar15. is there a way to remove and replace without loosing or removing the castle nut?

[QuarterBoreGunner]

Short answer: no

Castle nut secures lock plate, lock plate secures buffer tube and detent spring... knee bone is connected to the ankle bone, etc.

[bartt]

Couldn't you insert a punch of the correct diameter from the left side (to hold the detent back) as you remove the pin from the right side ? Then reverse the process to insert the new pin..?
I've never done it this way, just speculating..

[QuarterBoreGunner]

There's no way to access the detent from either side; it's in a channel inside the right rear of the receiver... maaaaaaaybe with a dental pick from the right side with the takedown pin partially pulled out.
Sounds like a hassle.

[BONECUTTER]

Couldn't you insert a punch of the correct diameter from the left side (to hold the detent back) as you remove the pin from the right side ? Then reverse the process to insert the new pin..?
I've never done it this way, just speculating..

Might be possible...you would need some kind of small hook needle tool to go in the takedown pin canal and push the detent down while you roll the pin. Then you need to be super careful with the punch because if the detent comes out putting it back without removing the castle nut would be very hard.

[calixt0]

ok thanks.. went out and bought a castel nut wrench... figured i would need it anyways sooner or later

[QuarterBoreGunner]

^Best solution.