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Is it possible to convert an M&P back and forth between 40SW and 357Sig with just a barrel/recoil spring/magazine change or is there more to it than that?



I'm trying to decide between the 40 and the 45. My preference is with the 45 but if I can swap between 40 and 357 sig on a 40 pistol I may go that route.



Thanks.



BC
 

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Sholling is right... all you need to change is the barrel to switch from .40 to 357. The recoil spring is the same. I was actually surprised to learn that the recoil spring assembly is even the same for the 9mm (though note that you can't shoot 9 with just a barrel swap).
 

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Y'all are saying that the only thing I need to do in order to fire .357 Sig from my .40 M&P is to purchase a .357 Sig barrel for it?... That's just another huge bonus for me with what has already become my favorite handgun.



I had actually been tossing around the idea of buying a pistol in .357 Sig, but with several .45's, several 9mm's, two 10mm's, a .45 Colt, and a few other misc. calibers of handguns... My wife would kill me if she thought I bought a new gun in a different caliber. A new barrel, however ... Hehehehe! :twisted:
 

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A new barrel and slide will convert you to 9MM also. That makes 3 in one and you can still say you are only buying repair parts.



:twisted:
 

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even if I have a 20c would a full size s57 barrell work in it? Or do they have a 357 compact barrell yet?
 

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cmdbass,

I think the fullsize barrel will not work in your compact. The barrels have a reduced diameter a little ways back from the muzzle and I am afraid that the fullsize barrel would not lock up tight in the compact slide. Take a look at your barrel about 1/2" back from the muzzle and you will see what I am talking about.
 

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gotcha.. that is what I was thinking but I just needed to hear someone tell me :)
 

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TOF, do we have a vendor/sponsor that carries the 9mm slide and barrel? Might be nice to be able to switch back and forth?
 

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I think this has been answered already but I am going the opposite direction...I have a 9mm full size.



To change to .40 or .357 all I need to get are the barrells and slides and magazines in .40 and .357?
 

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Note - this is not unique to the M&P 40. As far as I know any brand .40 can be switched to 357 Sig with just a barrel swap. This is because 357 Sig is a .40 case necked down to hold a 9mm bullet. That is why you can use the same magazines.
 
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