M&P - .40 in a 9mm?

TimeAttack

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Does anyone own an M&P .40?

I'm wondering if the magazine 'fits' in an M&P9 and also how many 9mm bullets you can fit in the .40 magazine.

From what I understand, if you bend the feed ramps a bit it will function fine with 9mm ammo.

Thanks
 
Does anyone own an M&P .40?

I'm wondering if the magazine 'fits' in an M&P9 and also how many 9mm bullets you can fit in the .40 magazine.

From what I understand, if you bend the feed ramps a bit it will function fine with 9mm ammo.

Thanks

Don't know if I'd what to alter a magazine, and then use it with more than 10 rds, legally speaking.
 
TimeAttack,

I have heard many people claim that a .40 magazine will fit 9mm ammo. I mean, the .40 isn't THAT much larger, right?

I've tried this on my P226s - one is 9, one is .40. The .40 magazines will NOT hold 9mm rounds - they just spit them out. Might hold one for a while but if you shake it or make any quick movements, it won't. If you put another round in, it won't. Maybe I lack the technique.

I would imagine that bending the feed lips of the magazine (I'm assuming you meant feed lips?) you will reduce the reliability of the magazine and perhaps even ruin them.

I'll let the M&P owners here chime in, but if it doesn't hold 9mm in a stock .40 magazine, the chances are slim and probably not worth it.

Hope this helps.
 
the stock 40 mags will hold about 12-13 rnds of 9mm but not very well if you hit or even tap the mag they all come out.
bending the feed lips inward may work but would be illegal FWIW
 
Maybe you shouldn't ask questions here because in many cases you won't like the answer.

If you want the correct answer than call the CFC and ask their opinion..:kickInTheNuts:[

why? its a perfectly legal question. there is no intent in this case. and FWIW, my friends glock .40 mags hold more 9mm's than my glock 9mm mags. its 100% legal, i just dont see the point in using them cuz 10 rounds is alright with me (im a 1911 guy at heart :D)

as for the OP, i have an MP 45. so I can't help you there.
 
why? its a perfectly legal question. there is intent in this case. and FWIW, my friends glock .40 mags hold more 9mm's than my glock 9mm mags. its 100% legal, i just dont see the point in using them cuz 10 rounds is alright with me (im a 1911 guy at heart :D)

as for the OP, i have an MP 45. so I can't help you there.

You are quoting the wrong guy. I never used the words LEGAL or INTENT, the other guy did............
 
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You are quoting the wrong guy. I never used the words LEGAL or INTENT, the other guy did............

sorry, had a long day!

now the Glock .40 mag is designed for a Glock .40.
Just like the LAR-15 10 roundmag is designed for the LAR-15 10roundmag.

The design is fine and legal, you can use them in whatever gun you use. Common sense with our laws hardly ever prevails! lol
 
Either way it kinda seems like a dumb idea to bend and modify a mag to make it work where it's not designed to. You are only asking for malfunctions and people often forget that a firearm is a bomb in your hands so why mess around.
 
Either way it kinda seems like a dumb idea to bend and modify a mag to make it work where it's not designed to. You are only asking for malfunctions and people often forget that a firearm is a bomb in your hands so why mess around.

well again for what its worth, i did not have to modify the glock mags what so ever. you just shove the 9mm's in. but speaking for MP's, I have no idea.
 
Thanks for the info, pretty much exactly what I was looking for.
I might pick up a mag and try myself now that I know it's possible.
I might accidentally drop it several times, it would be terrible if that happened to hold 9mm rounds in the mag as an unintended consequence.
 
For what it's worth, I don't see any prohibition on carrying 13 9mm rounds in a magazine designed for ten .40 SW, even if you modify the magazine to do so. The regulations, I believe, prohibit "Any cartridge magazine... that is capable of containing more than 10 cartridges of the type for which the magazine was originally designed and that is designed or manufactured for use in a semi-automatic handgun that is commonly available in Canada.

Those of you who have said it is illegal must know something that I don't see. Gents?
 
Does anyone own an M&P .40?

I'm wondering if the magazine 'fits' in an M&P9 and also how many 9mm bullets you can fit in the .40 magazine.

From what I understand, if you bend the feed ramps a bit it will function fine with 9mm ammo.

Thanks

read the thread.
was interested to know the answer, so i went upstairs and took out my 9 and 40 and tried.
the mags are interchangeable.
which dosnt surprise me much as the guns are totally identical.

but to answer your question.... yes.
the 40 cal mag fits in the 9mm perfectly.
 
My M&P 40 cal mags will hold 12 rounds of 9MM. Bump the mag and it doesn't hold any very quickly. The gun will feed them ok. IDPA and IPSC have 10 round lmits so I don't bother.

Take Care

Bob
 
Good info on the .40 to 9mm. Is it possible to go from 9mm to .40 with
the M+P if you could purchase the right/different barrel?

You can drop 9mm mags and barrel in the 40 but 40 into a 9mm doesn't work so well. Something with the spring on the guide rod apparently they are different.
I tried it and kept getting failures.
Going 40 to 9mm barrel and mags worked like a charm.
 
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