MP-Pistol Forum banner

.40 S&W damages pistols - M&P's, too, or not?

4K views 28 replies 15 participants last post by  DHart 
#1 ·
I've seen a thread on a couple other forums about some police department having to replace many of their Glock pistols in .40 S&W due to frame cracking.

Has that ever been an issue with M&P pistols?

If it's a .40 S&W issue (the pressure of the round is quoted as being higher than 9MM in these other threads) then why don't the .357 SIG pistols have the same issue?

Just curious if anyone knows of issues with M&Ps due to the cartridge/caliber.
 
#2 · (Edited)
Others who are way smarter than I will be along to give you the better answer, but the .40S&W is not a high-pressure round, I think it's the same pressure as the 9mm. The .40S&W (in my opinion) has a faster energy spike than the 9mm which cause some to feel that it has more recoil or is more snappy...

I just left the world of Glock, been carrying Glocks since the early 1990's, and everyday for the last 9+ years. I have not seen the .40S&W break any Glock frames, nor have I heard of such a thing, and I see allot of Glock 22's (.40S&W) everyday. I have on occasion witnessed a Glock 22 go down because it has broken a smaller part, but that too is not a everyday occurrence.

The MAIN REASON, besides ergonomics, that I recently switched from Glock to the M&P is that the M&P was designed to handle the .40S&W, which makes it a very strong auto.

UP-DATE: well I was wrong, went and took a peak at "Glock Talk" found this link where a small PD found hairline fractures in their 2000 vintage Glock 23's, I stand corrected sir... link: http://www.wdrb.com/story/29078319/bardstown-police-replacing-guns-after-dangerous-defects-found
 
#4 ·
I'm building my M&P 9mm into a USPSA Open Gun this summer... Pushing 124gr bullets at close to 1400FPS (9mm-Major). These guns run just fine... M&Ps are built to withstand a LOT of pressure with fully supported chambers, and plenty of "meat" in the chamber area, and in the locking lugs.

JW
 
#5 ·
Pressure will not crack frames so the rumors aren't addressing any alleged problems with Glocks. Pressure mainly affects the chamber which is part of the barrel assembly. If the 40 S&W rounds are causing cracks in the frames compared to 9mm, it's the recoil of the round that is doing it. This is possible if the frame is not up to the task.

A rough estimate says 180g 40 cal bullet with a MV of 1000 fps produces 36% more recoil than a 120g 9mm bullet at 1100 fps. This is just the bullet, not the combustible product exiting the muzzle. The plastic ought to be able to handle this banging of the slide against the frame and frame inserts but if it can't, then it makes sense that 40 is more punishing to the frame than 9mm.

My M&P 40 has somewhere around 20,000 rounds through it and I don't see any fatigue or cracking in it. I wonder what the round count is in the failed Glocks.
 
#7 ·
A rough estimate says 180g 40 cal bullet with a MV of 1000 fps produces 36% more recoil than a 120g 9mm bullet at 1100 fps.
Why not use the actual numbers, instead of just making stuff up, especially since few people will ever shoot 120gr. 9mm bullets.

Speer Gold Dot:
40S&W 180 gr. 1025 fps, 420 ft./lbs.
9mm 124gr.+p 1220 fps, 410 ft./lbs.

Federal HST:
40S&W 180 gr. 1010 fps, 408 ft./lbs.
9mm 124gr.+p 1200 fps, 396 ft./lbs.

Ah, that's why you don't use actual numbers.

BTW, these are their most popular defensive round per caliber.
 
#6 ·
Spike would be from powder. Bullet set back, regardless of powder will increase pressure (One reason OAL should always be respected).

A bullet set back toooo far with an unsupported chamber COULD result in personal injury.

Otherwise, M&P 40 is golden, relax and shoot on!

eb
 
#10 ·
I know his name's blasphemy in many circles, but James Yeager has elaborated on this subject for several years. Like him or not, he seems to have a pretty good handle on these issues.
 
#18 ·
I just bought one of those 2 cavity Lee molds a couple months back (haven't used it yet).

My CZ P09 really seems to like 115 grain hollow points so I thought I'd try a cast bullet near the same weight.

My M&P 9MM shot the heavier bullets really well. They're all different.
 
#19 ·
No cracks in any of my M&P357.
 
#20 ·
I also like the TL356-124-2R 6 cavity mold. It may not be a great mold for TL, but it works well for powder coating and even though the bullet comes out of the sizer with flush driving bands, it shoots just fine. If you want to expand the cases without swaging down the bullets, look into getting the Lee 38 S&W expander plug for your PTX die. It acts like a Lyman "M" die but costs only $3.

 
#21 ·
I've seen a thread on a couple other forums about some police department having to replace many of their Glock pistols in .40 S&W due to frame cracking.

Has that ever been an issue with M&P pistols?

If it's a .40 S&W issue (the pressure of the round is quoted as being higher than 9MM in these other threads) then why don't the .357 SIG pistols have the same issue?

Just curious if anyone knows of issues with M&Ps due to the cartridge/caliber.
wow did this tread go side-ways...so I posted the OP's original post... :smoke:
 
#22 · (Edited)
Well, the recoil difference is actually 41% and not 36%. My original estimate was simply a % difference in momentum calculations. Here is a more detailed run through Quickload <pic attached below>.

I apologize to the OP for the direction of the tone this thread has turned. I was simply trying to help figure out what could be the cause of the Glock frame failures. I still contend that chamber pressure would have nothing to do with the polymer frame cracking on a gun with normal use and that a typical 40 round has more recoil than a typical 9mm round.

He doesn't need to worry about similar problems with M&P's if they occur. First of all, it really shouldn't happen, secondly Smith and Wesson guarantees the M&P's with a lifetime warranty. I've benefited from getting replacement parts from them that were covered (slide lock, recoil spring, magazine springs).

And now you're a physicist? Cool.
No, but I stayed at a Holiday Inn last night :)

No, in fact I do have a bachelor's degree in Physics and a Master's in Scientific Instrumentation, no PhD, just enough physics knowledge to be dangerous and have fun. I don't like to brag, but you assed.
 

Attachments

#23 ·
#26 ·
My comments are only annecdotal, but my Glock 23's have felt uncomfortable, to me, shooting .40S&W.

Quite the contrary, my M&P40C and M&P40 both fire .40S&W very comfortably and with no apparent difficulty. One thought... if any gun maker should be able to design a pistol to fire .40S&W quite competently, it SHOULD be S&W!

While I am very much a fan of Glock nines and forty-fives, when it comes to .40S&W, I definitely go directly to the M&P40/40C. I think .40S&W, as a caliber, makes a lot of sense... it offers a great balance between the power of .45ACP and the capacity of 9mm.

While my STI Edge in .40S&W makes shooting .40S&W feel like mere 9mm target ammo, the M&P40/40C make carrying .40S&W as a CCW (defense gun) perfectly wonderful.

My G23 and G22 are safe queens.
 
#27 ·
My comments are only annecdotal, but my Glock 23's have felt uncomfortable, to me, shooting .40S&W...
The "feel" of the Glocks is very much "un-ergonomic". I've told many friends that controlling a Glock was akin to holding the fat end of a baseball bat. I've handled and fired a number of Glocks, and never thought that the .40 S&W models were any worse than other calibers. The exception has been the single stack G42. The H&K's, Springers, and Sig's are no better.

The "problem", if you will, is the need for double stack magazines. I get the desire for more ammo, but most all double stacks have a grip width of at least 1.25" (some 1.5" and larger), and circumferences of over 6". For folks with large palms and short fingers, it's a real show stopper. It's a primary reason why I've always liked the 1911 pistol.

I've tried a number of SFP's, and the S&W M&P pistols are the most comfortable handling. I regularly carry a M&P 40 Shield and a Compact. My only complaint has been that the Compact is just a bit short in the grip, but it's not too snappy for control.

With that in mind, I found a full-size M&P 40 Pro C.O.R.E in the used case at a gun shop about 60 miles from here. At the price, it was too good to ignore. The gun is in mint, NIB condition. It hasn't even had an optic mounted. It was shipped in April 2013. I changed out the original back panel with the smaller one, and it fits my hand perfectly.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top