Topic: Sig 228/229 Question

[MtGoat]

Are the Sig 228 and 229 lowers interchangeable?  Are the railed and non-railed lowers interchangeable?

To make a short story longer:
I have a Sig 229 STC.  I really like the gun but can see no use for a rail on a smallish carry gun.  I wouldn't mind losing the rail so am looking for a donor gun as I can only find railed lowers for sale.  The railed gun can be a shooter for my daughter.  I found a decent price (read as, not a great price but decent). 
As long as I am swapping around thought maybe I would look for a 40 S&W that way I can swap calibers (but would lose the green weenie front sight of the STC).
Are there any issues with trading the lower (frame) between guns as long as I keep the barrel and slide (upper assembly) together or are there fitment issues with Sig's?

Thanks
Pat

[telomere]

From what I have heard, you're not the first guy to ask this.

Everything I have seen said it's a no-go, but I could be wrong.
Even if they seem to fit, there could be tiny little differences which could cause big problems.  Probably not worth the risk.

Maybe someone else here knows more about this than I do though.