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Discussion Starter #1
WHAT!? A bi M&P? O man I hope so.... :wink: Fun.. fun..




On the serious side... Whats the difference in the .40 and the .357?

Looks like same frame, same mag etc.. Can you plop a .357 bbrl and a diff spring in a .40 and it work? Some Glooks (my post Ill spell it any way I want) are bi. (buy they just dont turn me on
) Why not the M&P. Just the idea gets the old blood going.




Just had to ask. 2 choices are better than one.
 

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Discussion Starter #3
I see Dan B on line... bet he knows!
 

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the part numbers are the same for everything on the 357 sig as the 40 except the barrel. .
 

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Discussion Starter #5
I looked too. And a light bulb went on, damn thing bout burned my hair! :roll:

I'm trying to envision the thing in CAD in my head. With the same frame and mag it would be smart to thicken the .357 bbrl to use the same slide saving money in the mfg process. If that is a given the bbrl ought to be the exact same legnth to use the same frame and mag.

Result= ought to work... at least in the CAD in my head.




"Are you pondering what I'm pondering?" :wink:



Note to self; Need MSN messenger of Jester and Dan B. to speed up the communication lag. Ah yes... a nice 3 way voice chatt.
 

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I haven't tslked to Smith about it and I haven't seen a 357sig to try it yet, but from everything I can tell it should be a straight barrel swap. But, I will caution you even though the springs are the same part number it is also listed as the same for the 9, I would certainly use a aftermarket guide rod and stronger spring.



Back in the day I owned a brand G in 40 and when the 357 sig came out I just had to try it so I got a barrel and dropped it in without a recoil spring change and ended up breaking my extractor in pretty short order. So since then I recomend at least inceasing the spring rate by 2-4 pounds.



Dan
 

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Discussion Starter #7
O baby! I think we got somethin here!
 

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Dan Burwell said:
I haven't tslked to Smith about it and I haven't seen a 357sig to try it yet, but from everything I can tell it should be a straight barrel swap. But, I will caution you even though the springs are the same part number it is also listed as the same for the 9, I would certainly use a aftermarket guide rod and stronger spring.



Back in the day I owned a brand G in 40 and when the 357 sig came out I just had to try it so I got a barrel and dropped it in without a recoil spring change and ended up breaking my extractor in pretty short order. So since then I recomend at least inceasing the spring rate by 2-4 pounds.



Dan


YEP!!
 

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I called Smith on Tuesday about the .357 sig "conversion." I was told:

1) It is as simple as a barrel change.

2) No, they won't sell me one. The person that I spoke to said that it would probably be at least a year before the barrel was available for anything other than repairs or warranties.
 

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Discussion Starter #10
#@$%!
 

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ledge said:
I called Smith on Tuesday about the .357 sig "conversion." I was told:

1) It is as simple as a barrel change.

2) No, they won't sell me one. The person that I spoke to said that it would probably be at least a year before the barrel was available for anything other than repairs or warranties.


By that time Barsto will be making conversion barrels, or EFK, or someone....probably as good and cheaper than Smith. :?
 
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I called Barsto and they have no plans to start making M&P barrels, yet. If enough of us call and ask perhaps those plans will be made.
 

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357 Sig barrel

You could use a 9mm barrel and ream it for 357 Sig and open the feed ramp to match the 40 wider shape add a new rod and spring, if you don't want to wait. FYI Brownell's sells the .357 reamer for $55.00 and then you have machine shop time and labor. Be for you you proceed, check the head spacing. If you are good with your hands its a weekend project. Test fire using sand bags to support the pistol and a firing string and stand back.. After 3 successful firings with no signs of over pressure you should be good to go. If your not a do it yourselfer don't attempt to do this without seeking professional assistance. Also look at your extractor after each firing to ensure you have not caused chips or cracks on the extractor tooth. Good Luck P.S. I'll wait for a factory! barrel :roll: :roll:
 

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I'd say the breech face is to small on the 9mm to stick a 40 size case head in. Never tried it, but I'd bet thats the case.
 

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I have a Glock 32; and a G23 barrel to go with it.

I have a Glock 22; and a G31 barrel to go with it.

I used to have a G27 with a G33 barrel also.

For those that don't know the G22, G23, and G27 are .40. The G31, G32, G33 are 357Sig.

In .40/357Sig Glocks, the only parts that are different are the barrel and the magazine follower.



As far as recoil spring assemblys go.

The G17, G22, G31, G37 all use the same recoil spring assy

The G19, G23, G32, G38 all use the same recoil spring assy.

The G26, G27, G33, G39 all use the same recoil spring assy.



I have never had a problem converting .40 Glocks to 357Sig and vice-versa. I have never had to use different springs either.

The early Gen 2 Glock .40s can not be converted to 357Sig. When the 357Sig came out, Glock changed a few things to handle the round; Glock also made the changes in the .40s to make everything compatible (except the barrel and mag follower).
 

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357 Sig barrel

Your right on Jester, thats why I mentioned you have to open the ramp to accommodate the 40 casing, Tks for checking me out.
 
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