Are 9mm and 40 M&P Recoil Rod/Spring Assembly The Same?

[curlysir]

According to everything I have read the 9mm and 40 M&P Recoil Rod/Spring Assembly are supposed to be the same.

I have a 9mm and a 40 M&P both bough in the last 3 months, both are 4.25" Pro models. The 40 has a spring assembly with green paint on the spring and the 9 mm has blue. I recently bought spare spring assemblies from Speed Shooter and they are listed as M&P 9/40 Recoil Rod/Spring Assembly. They have blue paint on the spring.

Is S&W now using different spring assemblies on the 9mm and 40?

If not why would the 2 assemblies have different color markings?

 

[mkbruce]

They used to be the same, but newer production uses different springs - one blue and one green.

 

[curlysir]

They used to be the same, but newer production uses different springs - one blue and one green.

That is What I thought. Glocks use different springs for the 2 calibers was suprised that S&W did not. Now to find some that has the 40 in stock. Speed Shooter just recently got the ones I bought back in stock. Have owned Glocks for years, just recently became a S&W owner. Parts availability is one of the biggest differences I have found so far.

 

[Biscut]

That is What I thought. Glocks use different springs for the 2 calibers was suprised that S&W did not. Now to find some that has the 40 in stock. Speed Shooter just recently got the ones I bought back in stock. Have owned Glocks for years, just recently became a S&W owner. Parts availability is one of the biggest differences I have found so far.

Maybe I'm wrong but I believe gen 1, 2, and 3 Glock's used the same recoil springs for at least the 19/23 and 17/22's and 26/27's.

Like you, my Pro's have difference colored springs. Sure does make sense to me considering the big difference in pressure between 9 and 40.

 

[curlysir]

Maybe I'm wrong but I believe gen 1, 2, and 3 Glock's used the same recoil springs for at least the 19/23 and 17/22's and 26/27's.

Like you, my Pro's have difference colored springs. Sure does make sense to me considering the big difference in pressure between 9 and 40.

I know my Gen 4's are different, I will have to check on my Gen 3 G22. OK, I checked Gen 2 and Gen 3 do use the same on the 9 and 40. I am surprised with the different in recoil between the 9mm and the 40.

 

[handgunner356]

The M&P 40s' use a heavier slide than a 9, the reason they can use the same spring. Just one other reason I don't care to use a conversion barrel in my guns.

 

[randyr5]

All of the usual suspects (Midway, Brownells, Speed Shooters) show the same recoil assembly for the 9 and 40.

I've read that the green is for the .357 Sig, but will also work with the 9 and .40.
The blue is for 9 and .40 only.

 

[curlysir]

All of the usual suspects (Midway, Brownells, Speed Shooters) show the same recoil assembly for the 9 and 40.

I've read that the green is for the .357 Sig, but will also work with the 9 and .40.
The blue is for 9 and .40 only.

Ordered and received a S&W M&P Guide Rod Assembly for the FS .357SIG from G & R Tactical. It has the green on the end. Other the the color on the end I can not tell any difference between the two. Still don't understand why they are marked differently. I wish S&W would mark their guide rod assembly like Glock does.

 

[DocSunShine]

The M&P 40s' use a heavier slide than a 9, the reason they can use the same spring. Just one other reason I don't care to use a conversion barrel in my guns.

BS, .40 & 9mm slides are virtually the same weight.

OP, as another already pointed out RSA used to be the same (blue spring) now they come with the green spring which used to be exclusive to the .357sig. However, blue spring should run .40 & 9mm just fine. .40 & 9mm also use the same extractor and ejector unlike with Glocks, which is why many find a 9mm conversion barrel with 9mm mags and .40 slide provide stock reliability.

 

[DocSunShine]

Ordered and received a S&W M&P Guide Rod Assembly for the FS .357SIG from G & R Tactical. It has the green on the end. Other the the color on the end I can not tell any difference between the two. Still don't understand why they are marked differently. I wish S&W would mark their guide rod assembly like Glock does.

Blue spring is approximately 15lbs., green spring is approximately 17lbs. I wouldn't advise using green with 9mm but blue should be GTG with .40 or 9mm.

 

[handgunner356]

Dear Doc, Weight them then look inside along the barrel, 9mm slides have less material in the side walls.

 

[DocSunShine]

Dear Doc, Weight them then look inside along the barrel, 9mm slides have less material in the side walls.

I no longer own a stock 9mm, however when I did I detected virtually no difference visually or comparing both side by side in hand. Per S&W Website .25oz weight difference between the models which is basically nothing. Myself and others have had very good luck with 9mm conversion barrels and OEM 9mm mags. I own a storm lakes for my full size, will likely be buying a compact version and the KKM for the Shield (when it comes out later this year).

 

[curlysir]

Dear Doc, Weight them then look inside along the barrel, 9mm slides have less material in the side walls.

Not Doc, but here are my results:

.40 slide 13.70 ounces, 389 grams

9 mm slide 12.95 ounces, 367 grams

barrel and spring assembly removed.

 

[DocSunShine]

Not Doc, but here are my results:

.40 slide 13.70 ounces, 389 grams

9 mm slide 12.95 ounces, 367 grams

barrel and spring assembly removed.

Thank you sir, 3/4 of ounce isn't going to make a difference. If you need evidence there is an abundance of members running cheap underpowered ammo flawlessly through their conversion barrels.

 

[uechikid]

I can't speak for current production, but my M&P40 that is a year and a half old a my daughters one year old M&P9 have the same recoil spring.

 

[Rastoff]

Sure does make sense to me considering the big difference in pressure between 9 and 40.

I used to believe that too, then I did some research. Both the 9mm and .40S&W have the same pressure standard; 35K psi.

The .40S&W has more recoil because of a bigger bullet.

 

[DocSunShine]

I used to believe that too, then I did some research. Both the 9mm and .40S&W have the same pressure standard; 35K psi.

The .40S&W has more recoil because of a bigger bullet.

Always fun debunked the "high pressure round" myth...

 

[Johnmuratore]

My .40c vintage 9/13 has a yellow-end recoil spring.
Is that the older one?

 

[Johnmuratore]

And thanks to Ras for saving us the .40 vs 9mm pressure angst once again.

 

[wittmeba]

I thought if you change the caliber you only needed to change the barrel and magazine. I haven't seen where there are springs to change with a barrel kit. Unless I am missing something...

StormLake S&W M&P .40 S&W to 9mm 4.25" Stainless Match Conversion Barrel SW-MP-9MMC-425-OP-00T