I just picked up a NIB Smith Walther PPK/S .380. Anyone have one? Any opinions? Number or rounds to break in? Any ammo advice? I'd like to use it as a summer carry. Thanks!

I had one many moons ago. Try a the ammo you intend to carry and see if you need to polish the feed ramp. You can bang away with any hardball to get used to it. A pretty nice little gun in my opinion.

Do you mean a Smith & Wesson version of the Walther PPK? Never heard of one from them.

Mine started to be reliable after about 250 to 300 rounds. At first it would malfunction almost every magazine and wouldn't function at all with hollow points. Now it shoots any hardball 100% but I have not tried hollow points again. It also had a burr on the mag release that made it hard to seat a full mag. I cleaned it up with a fine file and it is fine now. At first I was disappointed with it but it's ok now. I wouldn't buy another one. I feel for the price quality control should be better.

Do you mean a Smith & Wesson version of the Walther PPK? Never heard of one from them.
Yes. Smith is producing the guns here in the US under license from Walther. They extended the beavertail to stop hammer bite.