Converting 40c to 9mm

scwv67

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Barrel and mag switch is all that's needed. S&W 9mm barrel or aftermarket?

Thanks.
 
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seeing this information makes me wish i had purchased a .40 instead of a 9mm. Now the question is, why cant you go the other way? is it because of the slide being machined for a 9mm and not large enough for a .40?
 
seeing this information makes me wish i had purchased a .40 instead of a 9mm. Now the question is, why cant you go the other way? is it because of the slide being machined for a 9mm and not large enough for a .40?

Yep. 40 barrel with not physically fit in the 9mm slide.
 
Is the 9mm barrel in the .40 slide not too loosey goosey then?

what was said above would lead me to believe that, but .5mm on each side isnt too much concern, its tight in the chamber, its the extraction i would be worried about.

I dont see any reason you couldnt take your slide to a machine shop and have it milled to fit .40

or the question is, where can i get a replacement barrel and slide.
 
Is the 9mm barrel in the .40 slide not too loosey goosey then?

That's why companies like Storm Lake and KKM make specific conversion barrels in 9mm that fit more precisely in the 40 slide.

However, lots of people have had success with factory 9mm barrels in the 40 slide.
 
The extractor is soo close that the difference is pretty much unseen. 40 to 9mm or 9mm to 40. They both work flawless with factory 9mm barrels.

And for the record, my .40 converted to 9mm is more accurate than my 9mm is from the factory.
 
Here are two pics of the 9mm and the .40 in the slide. The first is the 9mm. You can see the gap between the barrel and the slide at the tab where the loaded chamber indicated is. When in use the barrel centers it self but I pushed the barrel to one side so you can see the amount of play between the barrel and the slide. The gap look big but it's only about 1/32". The second pic is the 40 in the 40 slide.
The question was asked if you can go 9mm to 40. You can if you are willing to remove a small amount of material from the tabs on a 40 barrel so it fits into a 9 slide.
My wife and I have been shooting with this setup for about a year with no noticeable difference in accuracy.
 

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That's why companies like Storm Lake and KKM make specific conversion barrels in 9mm that fit more precisely in the 40 slide.

However, lots of people have had success with factory 9mm barrels in the 40 slide.


Understood.
 
The extractor is soo close that the difference is pretty much unseen. 40 to 9mm or 9mm to 40. They both work flawless with factory 9mm barrels.

And for the record, my .40 converted to 9mm is more accurate than my 9mm is from the factory.

Factory or aftermarket barrel?
 
If you can find a factory barrel go with that. They are under $70 and they work great. The problem is, no one has them right now. The good news is, you can find 9mm magazines for very reasonable prices. If you're committed to doing this you should pick up a couple mags while you can. Just a few months ago 9mm M&P mags were going for upwards of $100 on ebay. Check out 44mag.com.
https://www.44mag.com/category/smith_and_wesson/a
 
I just dropped a threaded factory 9mm factory barrel into my VTAC 40. I haven't taken it to the range yet, but I am having a lot of failed to extract with snap caps.

Does the VTAC have a different extractor?
 
This might be one reason that M&P 9mm barrels are scarce right now.

Thats kind of what they "claimed" was the reason for the 9mm scarce.

Both of which i highly doubt are the effective reason.

Surely makes u wonder why .22lr has become so scarce. =-)
 
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I put a Storm Lake barrel in my .40, love it. I do use the .40 mag. but it won't feed the last round. Couldn't find a stock barrel. Going to get a few 9mm soon.
 
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