Getting an M&P trying to decide which one

EBK

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So I am leaning towords the FS .40 so I can get the .357 sig and 9mm (and mags of course) barrels and have 3 guns and one frame, My question is is this possible with the .45? I assume the frame is a tad bigger so its not but it never hurts to ask.

Forgive me if it has been asked before I went back several pages and did not see it.
 
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It will not work with the .45 ACP. If you get the .40, you can definitely do the .357 SIG. There are plenty of folks who get the 9mm barrels and magazines and they report it works most of the time. That said, S&W does not recommend it and since the .40 breech face is different in dimensions from the 9mm, you end up with sloppy extractor fit, and increased likelihood, upon ejection of a live round, for a wobbly round to strike the ejector. Remember, when a sharp, pointy thing hits the primer, you get a discharge. A discharge is not bad with a chambered round and the sharp, pointy thing is the firing pin upon you pulling the trigger. The ejector firing a round, and it is well documented that this happens (thankfully, rarely), is not good as, by definition, the round is not chambered and there is nothing to contain the pressure and injury will or can occur. Thus, be cautious if you try to fire 9mm out of your .40. If you want to shoot "on the cheap," get an M&P in 22 LR.
 
It will not work with the .45 ACP. If you get the .40, you can definitely do the .357 SIG. There are plenty of folks who get the 9mm barrels and magazines and they report it works most of the time. That said, S&W does not recommend it and since the .40 breech face is different in dimensions from the 9mm, you end up with sloppy extractor fit, and increased likelihood, upon ejection of a live round, for a wobbly round to strike the ejector. Remember, when a sharp, pointy thing hits the primer, you get a discharge. A discharge is not bad with a chambered round and the sharp, pointy thing is the firing pin upon you pulling the trigger. The ejector firing a round, and it is well documented that this happens (thankfully, rarely), is not good as, by definition, the round is not chambered and there is nothing to contain the pressure and injury will or can occur. Thus, be cautious if you try to fire 9mm out of your .40. If you want to shoot "on the cheap," get an M&P in 22 LR.

Thanks for the advice.

" If you want to shoot "on the cheap," get an M&P in 22 LR" this part is a joke right? Cant even find .22 around here for any price.

I want the 9mm barrel simply because I have reloading dies and plenty of supplies for 9mm. Also I just read a thread on this site specifically asking if anyone had issues of any kind with the 9mm barrel in the .40 and no one showed up to state they had a problem with it.

If the 9mm conversion isnt safe I will start looking at another pistol as I already have an SD 40 that I carry and no desire to replace it. The prospect of having 3 pistols in one frame is what was making me lean towords the M&P line.
 
I wonder if Shawn can show us an incident where an M&P 40 using a M&P 9mm factory barrel actually had a round go off by hitting the ejector?

I'd say the tens of thousands of rounds that have been fired using a 9mm barrel in a .40 M&P is testing enough for me.

But if you are looking for a do-everything gun, you could get a 40c, and then get the barrels and the full size mags and have six guns in one frame. ;)


.
 
The 40c is probably the most well rounded gun in the M&P line. I really enjoy mine. I would have liked to get one without the magazine safety, but that is my only gripe.

If you are looking to target shoot I can't say enough good things about the M&P 22.
 
Just my opinion but if you want a .40 then get one. If you want a 9mm then get one of those instead. Your buying a firearm and not a swiss army knife. The engineers that designed these different guns didn't do it so you could swap all the parts around and Frankenstein your gun. That being said, I have never read a bad thing on hear about a swapped barrel. This is just my opinion.
 
Actually I could not argue more against that FF112173. Engineers who work on a product line strive for parts commonality. Its cheaper to manufacture and better for the customer. I applaud the S&W engineers who developed a firearm where I can go buy a handful of parts and have a non-permanent conversion.

When a product line goes out of its way to hinder that conversion to force the consumer to buy a nearly identical gun that is frustrating but certainly something S&W could have done.

As far as the M&P compact guns, it is proven that a barrel swap to .357 works just fine and with a magazine and barrel swap 9mm works just fine.
 
Perhaps it is proven and I do not argue that, but does S&W suggest this WBlacklidge? Will they warranty a firearm that breaks due to this? I doubt it. Just because you can doesn't mean you should. I can put a programmer chip in my Chevy pickup and it will work just fine. Thousands have with no problems but if there is a problem with your motor and they see the programming change, and they can, I'm s.o.l.

It's just my opinion.
 
Good point FF112173, I can't imagine they would accept to repair your converted firearm. Your original point actually makes a lot more sense when you have that in mind.

Just typing 'converted firearm' probably put me on an ATF list...

The conversions do work, I know nothing about S&W upholding a warranty after either conversion. Definitely a risk.
 
At this point I have over 11,000 rounds of 9mm through my M&P40 using the factory 9mm barrel and mags with no issues and I am not the only one to say this. I too would like to hear of a case where this conversion caused an unsafe condition. I am also using this same type of conversion with my Beretta 96fs also with no issues. If you compare a 9mm and a .40 cal rim there is about 3 hundreths of an inch difference. The 9mm case is not wallowing around in there. It was only a couple of years ago that a lot of guys were saying that the conversion was not possible at all. I'm not an authority on the subject but I feel that my 11,000 rounds without issue have made me feel confident about the conversion.
 
I was training one of my PD's reserve officers with his M&P 40 which he had swapped out with the 9mm components. On very few occasions he had issues with Failure to Eject. Once we swapped back to the 40 caliber the issues were no longer present. I like the idea of being able to switch out to different calibers with the correct components but watching that made me second guess. This weapon was purchased used and the reserve was more or less a first time shooter so there could have been some other causes of the issue. Just my experience with it. Good luck and enjoy!
 
I would have to guess that he was having other issues. I have never had a 9mm round fail to eject. Both the M&P9 and the M&P40 use the same ejector. I am honestly not trying to talk anyone into the conversion. Just stating what my own experience has been.
 
Lots of great comments, but I have one question for you, EBK: What job will your new M&P be doing? Concealed carry, plinking, home defense...effective ammo, readily available, stopping power? That should help you decide caliber and overall size.
 
BAM!!! There is the $1,000 question. Well played!!:cool:

Lots of great comments, but I have one question for you, EBK: What job will your new M&P be doing? Concealed carry, plinking, home defense...effective ammo, readily available, stopping power? That should help you decide caliber and overall size.
 
To answer the question of what it will be used for.
general purposes/ range gun.

I have a concealed carry gun S&W SD 40 w/ APEX carry/duty spring kit love it no need or desire to replace it.

I also have a 1911A1 in .45 and a taurus PT111 in 9mm (I carry this if I need deeper concealment) Also have a Walther P22

So lets break it down, I have the major calibers covered 9, .40, and .45 as well as .22

What I was looking for was a range gun that MAY be used for carry and I dont have a .357sig so being able to convert to that is a plus. I already own a .40 so the only reason i am looking at the .40 is because of the ability to swap to .357 sig and from my understanding through reasearch 9mm as well.

In short no real reason other than i want another gun and multiple calibers is a nice plus.

ETA also the M&P and SD line share holsters and sights so it means I wont have to buy as much stuff like a holster or some night sights as I already have them sitting around.
 
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As an owner of a new M&P FS .40. I like everything about it.

I had some minor issue with the take down lever and I wish the 15rd mags were available a little more often, but if I was to lose it in a "boating accident" I would make the same purchase tomorrow.

The more I shoot it the better it feels and the more I like it. This is my range and night stand gun.
 
I liked my FS M&P40 4.25" that I added a M&P40 Shield and a M&P40L 5" CORE I think I will pass on the 40 compact for now. Once you buy one you will want another.

I carry the Shield the most, but I still like the 4.25" on my hip or in my shoulder rig.
 
I recently got a mp40c and love it. I bought it with I tensions of getting the 357sig and 9mm barrel. I have actually got the 9mm barrel but have not tried it as I can't find any 9 mm ammo. I have grown to like shooting the 165 gr .40 ammo so I may never change the barrel. But at least I have the option.
 
Just my opinion but if you want a .40 then get one. If you want a 9mm then get one of those instead. Your buying a firearm and not a swiss army knife. The engineers that designed these different guns didn't do it so you could swap all the parts around and Frankenstein your gun. That being said, I have never read a bad thing on hear about a swapped barrel. This is just my opinion.

+1

If I was to do it all over I would choose one caliber (9mm) and buy all my semi autos around said caliber.

I would also pick up an M&P 22 LR for my wife and as a warm up weapon.

Russ
 
My original thinking was that you never know what the future is going to bring. Having a firearm that is capable of firing multiple calibers can possibly make the difference of having ammo or not. How many of you have walked into a store and found that they had 9mm but not .40S&W. Or vice versa. If this current shortage has tought me anything it's just how quickly ammo and supplies can become non existant. As in nature, being able to adapt is the key to survivability.
 
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