It's possible, like what's in the link that scoob gave. The change between 9mm and .40 should just involve the different barrel and a different magazine (assuming a .40 mag would fit).
*sigh* ... they just never listen to the ol' LT, do they .........40S&W and .357Sig are pretty much interchangable, just drop in a differnt barrel. Reliability may not be as high .....
Just got a P229 in 9mm. I heard it's relatively easy to change to .40 or .357. Do I just have to change the barrel? Do I need a different mag too?
It can take the 15 round P226 mag too, right? Didn't want to buy without double checking.
....You can go from the big bore to a smaller one, but not the other way around. This goes for all the Sig pistols....http://www.sigforum.com
Snake,
You were probably thinking of the Sig P228 (.40 cal)... This weapon can be kitted to convert to a .357. As far as I know theres no way to convert a 229 to either of these calibers. Too late to take it back?