Skip to content
View in the app

A better way to browse. Learn more.

New Jersey Gun Forums

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

M&P40 -> M&P9 - conversion barrel

Featured Replies

Greetings,

 

I have an M&P40 and have read that it will take a S&W M&P9 barrel and work. Anyone have experience w/ this? Does it work and work well?

Greetings,

 

I have an M&P40 and have read that it will take a S&W M&P9 barrel and work. Anyone have experience w/ this? Does it work and work well?

 

It will probably work, but there are issues. 1) Don't forget the magazines. 9mm in 40 mags does not run well despite potentially working poorly. 2) The breech face angle cut into the slide differs between 9mm and 40mm. This can cause issues for some people.

 

All the below reuire you to buy 9mm magazines.

 

Most reliable conversion - buy a 9mm top end. Midway sells them for about $250-260 for the plain old iron sigts. About $300 for night sights.

 

NExt best - buy a conversion barrel form storm lake. AFAIK, They cut the bore off axis to account for the breech face angle being different. It's 100% for most, 95% for a lot more.

 

Least best - buy a 9mm barrel and drop it in. YMMV.

You cannot use a stock 9mm barrel, you need a conversion barrel from Storm Lake or KKM. You will need 9mm magazines also. I have a 9mm conversion for my Sig P229 .40 and while it is reasonably reliable enough for training it is not reliable enough for defense purposes.

  • Author

It will probably work, but there are issues. 1) Don't forget the magazines. 9mm in 40 mags does not run well despite potentially working poorly. 2) The breech face angle cut into the slide differs between 9mm and 40mm. This can cause issues for some people.

 

All the below reuire you to buy 9mm magazines.

Already purchased mags. 15rnd'ers of course :icon_mrgreen:

 

Most reliable conversion - buy a 9mm top end. Midway sells them for about $250-260 for the plain old iron sigts. About $300 for night sights.

Excellent info. Didn't realize Midway sells M&P uppers.

 

should have bought a Glock!

Already have 5 (and still like them better than the M&P's, but want to use the M&P as an experimental platform). Should mention, I came across a used M&P45 for $360 OTD at Bullet Hole that has been bought. Just waiting on my permits. Should be very soon (hopes it's very soon). In handling the 45 (holding not shooting), the frame is just different enough that it fits my hands perfectly, whereas the 9/40 platform feels like it's almost there.

 

You cannot use a stock 9mm barrel, you need a conversion barrel from Storm Lake or KKM. You will need 9mm magazines also. I have a 9mm conversion for my Sig P229 .40 and while it is reasonably reliable enough for training it is not reliable enough for defense purposes.

 

I found this thread on ar15.com. From what a few people have posted, the M&P9 barrel will work reliably in a M&P40. I should say I picked up an M&P9 barrel, but won't be able to shoot it until the weekend after labor day. Very excited to see how this works.

I found this thread on ar15.com. From what a few people have posted, the M&P9 barrel will work reliably in a M&P40. I should say I picked up an M&P9 barrel, but won't be able to shoot it until the weekend after labor day. Very excited to see how this works.

 

That's interesting news, I stand corrected.

Not to change the subject, but how well does a 9mm conversion barrel work in a Glock 23?

  • Author

Not to change the subject, but how well does a 9mm conversion barrel work in a Glock 23?

 

I believe (don't know for sure) that you can not use a Glock G19 barrel in the G23 as there is enough of a difference in dimensions that it can't be used. Having said that, I believe companies like Lone Wolf, Storm Lake, etc., do make dimensionally correct conversion barrels for the G23 to shoot 9mm.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

Recently Browsing 0

  • No registered users viewing this page.

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.