Interchanging M&P slides and frames

General Firearms Handguns - Semi Auto
1

I have a M&P 9mm with 4.25" slide and am considering purchasing a Pro. I’ve tweaked my current frame with a trigger upgrade, stippling and such. I’ve compared my frame to a buddies Pro and they are identical, as far as I can tell. I put his slide on my frame and everything ran fine. Am I missing something?

What’s more, the description of the Pro says it has a 5" barrel and standard’s is 4.25". But it’s the slide that’s 5". The barrels are the same size. Even the guide rod positioning is the same. Again, am I missing something? Thanks

2

The M&P Pro comes I have both 4.25" & 5" versions…sounds like your buddy has a 4.25" version which is not much different than your standard model outside of trigger and sights.

3

Positively, he has the 5" version. I have a 4.25" - NOT Pro model.

4

Having owned a 5" pro and several 4.25" FS models, I can say that the barrels are indeed not the same size. Guide rods are the same but barrels no.

The frames are the same and you can indeed switch the top ends at will.

5

Just talked to my buddy. As your probably already aware, the barrel is longer. :slight_smile: Ooops!

Otherwise, i assume there is no issue with slide to frame fit.

6

Will a compact slide fit on a full size frame?

7

No.

But you can make stupid configs like so:

What can I say…I was bored.

8

Oh God why do I like the way that looks.

9

I have been interchanging the upper and lower between a 45 mid-size and full size, one with, and the other without, the thumb safety. Both have Apex DC triggers. Working fine so far.

10

It works fine.

Just keep in mind you’re inducing odd wear patterns between slides and frames.

This could lead to premature wear.

11

To be more precise, I should have said I interchanged, as opposed to interchanging, because I wanted the thumb safety on my mid-size. You see any issue with a one time switch?

12

No, absolutely not.

The parts are the same between pistols so going from one locking block and sear housing plus the slide to another should not make a difference.

Now, throwing a brand new slide on a frame with 50,000 rounds through it would probably be a bad idea. Replace your locking block and sear housing.

13

So I ordered a Pro with 5" slide and barrel and will put it on my existing 4.25" frame. I only have about 5,000 rounds on it, so I don’t think there should be a problem. Had to order a new kydex holster and went ahead and picked up Warren Sevigny sights with f/o front. UPS is making some money on me today!

I plan to sell the new, Pro frame with 4.25" slide.

14

u can NOT switch the 9mm uppers and lowers
i dont know about the .40 but would say not. have never owned a .40.

the .45’s they caught the error and corrected it. u can do it, i have also.

per Earnie Langdone before he left smith&wesson

good luck

15

I’ve personally switched a Pro slide onto a non-pro, 4.25" frame and ran multiple mags with no malfunctions whatsoever, in 9mm. If you hold both frames next to each other, you can’t tell the difference. They appear cut from the same mold.

Why exactly do you say you can NOT switch?

16

Um…

Can we get some further explanation?

The 9mm frames are all the same…

Same with the .40’s.

17

That mutant Pro/Compact setup I showed you? I ran 300 rounds out of it at the range, it works just fine, it feels like shit, but it shoots.

So gonna say sorry…but it works and they are interchangeable.

18

For that matter, the full size .357/40/9 frames are all the same.

19

Reminds me of an M&P version of an Hk USP Expert. Which, of course, would be awesome. :smiley:

20

I am mixed up by some of the replies. Are all the full size 9mm frames interchangeable? And a second question: Can I put a compact slide on a full size frame or will it not work and potentially lock it up like a glock?