If you have a P229 frame chambered in .40 S&W are there any limitations to what 9mm slides would work on the original .40 S&W frame? In this case, you are talking about a P229-1 magwell on a non-rail German made frame with a US made slide.

Second question, P229 stainless elite with a rail. Any limitations to a 9mm slide on the .40 S&W frame?

THANKS!

Some 9mm slides need a different locking block.
Excam has made some really good posts on this topic.

You can also use a P228 9mm slide on a P229 with a new locking block.