Re: Sig P239 Takedown Issue
Okay, I've looked a little more closely at what happens when we field strip our two (both P239 and P6). I think your diagnosis is spot on.
We can see that rotating the takedown lever down does push the recoil guide forward against the already-compressed spring (funny, I'd never noticed that before). I have a very easy time believing that if the guide rod were plastic, its head would be easily deformed.
That might explain why our P239, which we bought slightly over a year ago, has a metal guide rod.
Presumably, in the interval between when you bought yours and we ours, SIG found the plastic rod to be a problem and changed to metal.
I think you should give them a call and see what they have to say. Their customer service number is: (603) 772-2302