M&P 40/9 Conversion

Yes Magazine s 9/40-357 works fine ad long it is. an M&P FS only works with FS buy Compact will works with C and FS. yes the slided seems to work fine my 357 SigC shoots fine with 9mm and 40 C OEM Barrels and 9mm FS Magazine work great. Rowlette
 
tired to search as you suggested

Shaving a bit of the barrel is the ONLY change.

The extractor inside the .40 and the 9mm are the exact same part.

In the end, it costs just the same to convert .9mm to .40 as it does the .40 to 9mm. All you need is a barrel and magazine.

This has already been done. Pictures and details are in the other thread. Just use the search up top.

Smitty, I tried searching the forums for the backwards convert (from 9mm to .40) but couldn't find it. Any help would be great, I guess it is possible that it was removed.
 
Check the link below to my original .40 to 9mm conversion. Look on page 3 and u should find where a member converted his 9mm to .40. He took pics and a video of everything. Since then, several other people have done the same thing and now have a 9mm converted to .40. Follow his instructions and u should be just fine with the conversion.

This was with a Shield also, so the FS or the C's could be different. Keep that in mind.

http://smith-wessonforum.com/smith-wesson-m-p-pistols/280665-converted-my-shield-40-9mm.html
 
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Guys, I tried to order a 9MM Shield barrel from S&W today and was refused. Not even offered a waiting list. Was told that it does not fit, had to be S&W fitted, was not for sale to the public and finally just not available. I have purchased over $12,000.00 in Smith & Wesson over the years and bought a M&P 40, Shield 40 and Bodyguard within the past three months. I have been a loyal S&W (USA only) customer for 40 years. This really insults me being lied to by the factory. It is like they think customers are plain stupid and will believe anything. It is quite possible the end of my Smith purchases. If anyone else knows how to get past the wall at S&W for a barrel please let me know.

Does any of the S&W compact series barrels fit the shield?


I just received my S&W 9mm and 357sig full size barrels from Midway last week that I ordered 2 weeks earlier. You might look to see if they have any in stock for the c model. For under $70 it's worth a try.
 
Has anyone shot 9mm through their .40 frame from a bench? Just curious as to the accuracy results.
 
Where did you find the 9mm barrel, even Midway customer rep tells me they have no such item nor never have had a 9mm shield barrel in their system. Do you have to call Harry direct?
 
Wouldn't think so but thought I'd ask. I got my 9 barrel today just need to find mags

You can load a 40/357 magazine with 9mm rounds. All but the last round will shoot fine, the last one will FTF. A full-sized will hold 17, IIRC, so 16 useable trigger pulls.

EDIT: Just grabbed a brick of 22lr from Midway and added a .357 Sig barrel, too. And I recently finished my stockpile of 9mm and .40 (1k rounds each) :/ Now I have to find some bulk 357!
 
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I experienced jams and very erratic ejection when using .40 mags to try to feed 9mm. Also had trouble getting the rounds to stay in the magazine and not pop out. It was harder to insert the magazines. Using 9mm magazines made the 9mm conversion completely reliable. Others report that they have better luck.
 
Where did you find the 9mm barrel, even Midway customer rep tells me they have no such item nor never have had a 9mm shield barrel in their system. Do you have to call Harry direct?

This was for my full size. Not my shield. Sorry
 
New member here and luckily this is the first thread I've read because I was about to buy a SD9mm just to have a 9mm, but now there is no need since al I have to do now is buy a barrel for my FS M&P40
 
Haven't posted for a while....after reading all these positives on the M&P 9mm conversion, I just went to Midway and ordered An S&W 9mm factory barrel for my M&P 40. 66 bucks plus shipping... Ok, how about some feedback...looks like the 40 mags work but maybe a hang up once in a while...I hear using the same recoil spring is no problem... Looks like this could work out well...
 
New member here and luckily this is the first thread I've read because I was about to buy a SD9mm just to have a 9mm, but now there is no need since al I have to do now is buy a barrel for my FS M&P40

40 mags are possible but not as reliable just buy the 9mm mags and you wont know the difference you would think you bought a m&p9





Haven't posted for a while....after reading all these positives on the M&P 9mm conversion, I just went to Midway and ordered An S&W 9mm factory barrel for my M&P 40. 66 bucks plus shipping... Ok, how about some feedback...looks like the 40 mags work but maybe a hang up once in a while...I hear using the same recoil spring is no problem... Looks like this could work out well...
 
Just got in my 9mm fullsize M&P barrel for my M&P40 today...Compared all "OD' dimensions with the 9 and 40 barrels, then seated the 9 brl into the slide and reassembled the pistol...then loaded a 40/357 mag with a mixture of 9mm 125 Golden sabre, 124 Tap critical defense, and CCI aluminum blaser 115 tmj. Manually cycled the action all the way through with no problems at all. Took it to my farm range and proceeded to empty 15 rd.s I had in the magazine at 8" inch steels @ 15 yds. All hits, no problems. Took it back in, did breakdown and searched for anything wrong...No problems, no gliches...Looks like I have a 3 caliber (40/357sig/9mm) M&P now. Thanks MidwayUSA for the factory S&W M&P barrel at a great price...!!!
 
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