I bought a oem S&W 9mm barrel from Midway USA last month for $66.99. They're currently out of stock but can be backordered. Don't know how long the BO is.

Put the barrel in my M&P 40 and shot 50 rounds with the .40 magazines. Noticed that I had to make sure to seat the first 9mm round good in the .40 magazine or else the slide locked back with that last round still in the magazine. Other than that it shot great.

I called S&W direct to ask about this and was told they are not selling the barrels separately right now. They are being held for production, and to not expect to see them on the market for another 6 months.......

Looks like I will be looking for an aftermarket one as M&P owners selling on the various forums have proven very unresponsive and unreliable unfortunately.

Who is selling KKM conversion barrels?

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unrepentant M&P fanboy

Go straight to KKM's website. They ship same/next day.

I opted for the threaded version of the barrel and it has worked out great. It fits the slide extremely tight and shoots straighter than I can. I heard S&W is keeping all 9mm barrels for production and not selling any to the public. KKM is more but you won't be disappointed. I bought the 9mm magazine for mine and have not had an issue with it. In fact I think the 9mm barrel might even shoot a little straighter than the .40 does, they both shoot great. Keep in mind that S&W made two styles of barrels, one with and one without a collar by the chamber. KKM sells the newer style. If you have a barrel with a collar you may want to get the Storm Lake barrel which MidwayUSA sells.

I did not see any conversion barrels on their site

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unrepentant M&P fanboy

Start configuring M&P, 40 cal barrel. Select the size, then look in the OPTIONS drop down.

There it is.



Dave

Well I guess you have to be smarter than the website! Lol gracias señor!

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unrepentant M&P fanboy

Just ordered one direct from KKM - sticker shock for sure. My wife has a 40c - this will give her a chance to see if she likes the 9mm. Now to find a couple of mag's

Like the Post indicates, I just got my new KKM 40-9 mm Conversion barrel but I never thought of the Spring until I was actually installing the new barrel.
I can't help but wonder, shouldn't I be using a new, lighter Spring for the 9mm Barrel and Round? Also, can I shoot +p rounds with this setup or should I play it safe and avoid those? That's probably more of an opinion question, but an educated opinion is what I am looking for.
My most important question is with the Spring. Do I use the Stock 40cal. Spring with the new 9mm barrel and stock 9mm ammo. if I should get a new Spring, where do I get it please?

I converted mine with a stock S&W barrel from Midway, and I used the spring that was already in the pistol. No problems at all.

Is there a manufacturer that makes a 40S&W to 9mm conversion barrel for the Shield? I couldn't find one on KKM's or Storm Lake's website.

I believe the spring is the same in the 40c and 9c. My 40c with KKM 9mm conversion has been flawless in over 200 rds with just the barrel and magazine change using a mix of 90gr practice rounds and 124gr +p.