Drop in barrel question

Discussion in 'M&P Forum' started by seamuskrat, Jan 2, 2013.

  1. seamuskrat

    seamuskrat New Member

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    I have a M&P .40. I have read the barrel dot the .357 sig is a drop swap and to covert to 9 is also a simple aftermarket barrel swap and new magazine. Sound right?
    I'd love to have multi ammunition capable parts with minimal expense. Loving my.40 so far.

    Thanks
     
  2. psymmonds

    psymmonds New Member

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    Yes, yes, and yes. To convert to .357, you just need a new barrel. The .40 mags are modeled for .357 also. Says it right on the mag. 9mm on the other hand, you need a 9mm barrel and mags to go with it. 9mm will fit in the .40 mag but will be a little loose. I myself wouldn't chance it, I would get new mags to go along with it. You can buy S&W factory barrels off of midwayusa. Or you can go to this storm lake.

    http://www.storm-lake.com/products/barrel
     

  3. robocop10mm

    robocop10mm Lifetime Supporting Member Lifetime Supporter

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    The .357 mags are exactly the same as the .40 mags. The only "modification" is the stamp.
     
  4. sweeper22

    sweeper22 New Member

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    357sig and 40sw are going to be identical apart from the barrel.

    When converting down to 9mm you may need an actual '40 to 9 conversion' barrel, rather than just a plain old 9mm barrel. There can be some issues with how the firing pin and primer line up laterally in some guns due to the reduced casing diameter.
     
  5. seamuskrat

    seamuskrat New Member

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    Thanks! Now to find them in stock somewhere!
     
  6. austin92

    austin92 New Member

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    Looking to get an m&p soon and intend on shooting .40 and .357 sig from it but I'm wondering which gun I should buy and which barrel. Like ".357 m&p/.40 barrel" or ".40 m&p/.357 barrel"?
     
  7. coinbuyer

    coinbuyer New Member

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    Just an FYI They are the same. They literally run and assemble the same gun and then set the barrel to what the frame is stamped. I would look at two things. The price of the aftermarket or factory barrels. Is one cheaper or not. Also availability of the complete firearm. Before the "gun scare" the 40 was very available and inexpensive in the used gun market. Now it seems that when you do find the 357 Sig, it is less expensive then the others.
    I would buy the one you could get the best deal on and then buy the other caliber barrel.
    My ten cents
     
  8. austin92

    austin92 New Member

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    Good points. Thanks man
     
  9. jakil007

    jakil007 New Member

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    Just got the 4.25 9mm, where / how can I get other caliber barrels? I'm in north Idaho, and local shops seem out of the loop
     
  10. Rick1967

    Rick1967 Well-Known Member

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    I am suprised that you can swap between 9 and 40. I would have thought that the diference in case size would be a problem for the extractor. I would also wonder if the bolt face on the slide of a 9mm would be big enough for a 40 to fit into. Is this a non-issue then or is everybody just guessing?
     
  11. jakil007

    jakil007 New Member

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    Your right, can swap but only with a conversion kit, probably easier/cheaper to buy another firearm
     
  12. jakil007

    jakil007 New Member

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    Also should include that the conversion only goes 40-9, not 9-40
     
  13. austin92

    austin92 New Member

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    Correct me if I'm wrong but couldn't they also go from .357 sig to 9mm if they can go 40-9 and the 357 is a necked down 40?
     
  14. Sparrowe

    Sparrowe New Member

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    Yes, I would like to know where I can get a 9mm barrel for my S&W 40 Shield