Had a first today.

I've put together numerous AR-15 rifles and was helping a friend assemble a stripped PSA lower.

Everything was fine except the rear take down pin. It was like the detent in the take down pin was drilled too deep. The detent pin sat at least half way in the hole and when the spring was behind it I could not budge the pin, even when using a nylon punch and brass hammer. I took the spring completely out and the detent pin still held tight even without any tension behind it (until I tipped the lower up, obviously)

I suppose I could remove some of the inside metal on the detents with my dremel, but there's not much sense in making an out of spec part even more out of spec. So, we'll have to wait for PSA to send a new take down pin.

Just to be clear, the upper and lower were not together when the pin was stuck. Has anyone else had an issue like this before? I've always had good luck with the PSA kits so I was surprised with the issue.

I’ve had to clip the detent spring occasionally to make it work.

quote:

Originally posted by kilyung:
I’ve had to clip the detent spring occasionally to make it work.

Yeah, I thought about that, but when I took all the tension off the spring by loosening up the castle nut and receiver plate, and eventually removed it completely, the stinkin' pin still wouldn't budge with just gravity holding it in place, at that point I knew I was beyond clipping the spring.

I had 3 extra springs and detent pins, tried every combo of each, no joy.

If the detent pin drops that far in to the take down pin it does sounds like the pin is out of spec.