Hey guys. I know people are dropping 9mm barrels into .40 Shields (when they can find them) and having them function. But my question is has anybody had 1st hand experience taking a complete .40 slide, barrel, recoil spring and guide rod and putting it on the lower frame from a 9mm. I called S&W today to ask about the frame and they said the frame is the same for both calibers. But they say they do not recommend doing this and that they specifically do not sell barrels or slides because of guys doing this. Thanks for any input. Hope I’m not beating a dead horse, but I wasn’t able to find any threads dealing with whole slides being swapped, only barrels.
M&P Shield .40 slide and barrel on 9mm Frame
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I'm afraid I can't help with your specific question but maybe an answer to mine might help.
My ported 5" M&P came in yesterday and I just noticed that it has the 9mm barrel that it should have but the slide is marked 40L. I have not fired it but the lockup is tight and the barrel will not budge a thousandth of an inch while it's in battery. I don't care what it says on it as long as it will work right. Can anybody help us out? Thanks.
My ported 5" M&P came in yesterday and I just noticed that it has the 9mm barrel that it should have but the slide is marked 40L. I have not fired it but the lockup is tight and the barrel will not budge a thousandth of an inch while it's in battery. I don't care what it says on it as long as it will work right. Can anybody help us out? Thanks.
V0OBWxZS16
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Did they explain why they don't recommend swapping slide assemblies or were they worried about folks swapping just barrels?
Deadeye Dick
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Probably this ^^.
... or maybe they are just concerned about loosing money on the sales of complete guns?
If the frames are indeed identical how does the frame know whether it has a 9mm slide & barrel attached or a .40cal slide & barrel attached?
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Smitty357
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Yes they will swap over perfectly fine. I can tell u from hand experience. Beings i looked over, under and through both the shield 9mm and .4. Long before I let the world know you could swap the 9mm barrel into the .40 slide. The parts within the slides are pretty much identical, although not exactly. However swapping just the barrels has never caused an issue and we have been doing it since the shield came out. If u are swapping the slide and everything inside it, then once again there is no issues. The frames are identical. But IMO, the trigger pull on the older Shield seems to be a bit better. =-)
They dont sell the barrels (now days). Because they figured out that some us were a little smarter than the average bear lol. Of course they dont recommend doing any swaps, because they wouldnt want to be accountable if an accident ever ocurred. So really we cant blame them for that. But of course we have never seen any accidents or even heard of any due to barrel swapping. Give it another week or so now that i say this and the internet will be full of rumors claiming the factory swap caused problems lol.
They dont sell the barrels (now days). Because they figured out that some us were a little smarter than the average bear lol. Of course they dont recommend doing any swaps, because they wouldnt want to be accountable if an accident ever ocurred. So really we cant blame them for that. But of course we have never seen any accidents or even heard of any due to barrel swapping. Give it another week or so now that i say this and the internet will be full of rumors claiming the factory swap caused problems lol.
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They said that they did not recommend it because they could not say what the ATF would do since the serial number was for a 9mm. IMO it is just an excuse. They don't want to lose the price of another sale. Because I asked guy if the frame was the same before asking if I could swap the slides he was not very happy. He sounded like I had backed him into a corner and he had no option but to confirm what he didn't want to say. He sounded very disappointed when I said thank you and hung up.
uechikid
Member
S&W is missing the boat with respect to swapping calibers. Sig makes models specifically disigned to be able to do this.
Hey guys. Thought I would update the thread with my experience. I just picked up my 9mm Shield on Monday. I also got my hands on a .40 slide/barrel set. As Smitty and others have said here it worked flawlessly. No problems and it is sweet to have 2 guns in 1 for a fraction of the cost. What a fun gun to shoot!
V0OBWxZS16
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That is a very strange response. Is that the script or would another CS representative would have a different response?
How did you get your hands on a slide/barrel set?
Just the right time right place I guess. I became interested in the shield about a month ago and started looking for one on calguns.net. Found a shield 9mm NIB from one seller and also the .40 slide and barrel set from another (in the private parts and accessories forum).
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busy2mch1
Member
THE answer
OK, folks. It's an ancient thread, but I have the definitive answer.
You CAN swap JUST barrel and slide, but you need .40 mags for the .40 to shoot, and vice-versa for the 9mm. ALSO, swapping JUST the barrel and slide CAN cause cycling problems, because the recoil spring in the .40 is just a bit stronger. On newer models, the spring colors are different. I believe it's BLUE for the .40 and GREEN for the 9mm.
Your BEST bet is to swap a complete slide with recoil spring, but swap the mags as well.
OK, folks. It's an ancient thread, but I have the definitive answer.
You CAN swap JUST barrel and slide, but you need .40 mags for the .40 to shoot, and vice-versa for the 9mm. ALSO, swapping JUST the barrel and slide CAN cause cycling problems, because the recoil spring in the .40 is just a bit stronger. On newer models, the spring colors are different. I believe it's BLUE for the .40 and GREEN for the 9mm.
Your BEST bet is to swap a complete slide with recoil spring, but swap the mags as well.
Better still, buy the firearm you want and don't Bubba it.
M1A4ME
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I have a couple .40 S&W Shield slides.
One has the original .40 S&W barrel and recoil spring assembly in it. Works great on a 9MM frame.
The other one has a .357 SIG barrel and .40 S&W recoil spring assembly on it and also works fine on a Shield 9MM frame.
Just need the .40 S&W magazines.
The .40 S&W slide/barrel/RSA also works on a Shield Plus frame - if you have a magazine or two that works with .40 S&W. You have to make those yourself by modifying the 9MM Shield Plus mags.
One has the original .40 S&W barrel and recoil spring assembly in it. Works great on a 9MM frame.
The other one has a .357 SIG barrel and .40 S&W recoil spring assembly on it and also works fine on a Shield 9MM frame.
Just need the .40 S&W magazines.
The .40 S&W slide/barrel/RSA also works on a Shield Plus frame - if you have a magazine or two that works with .40 S&W. You have to make those yourself by modifying the 9MM Shield Plus mags.
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