Rust E. Badge
Member
- Joined
- Jun 24, 2016
- Messages
- 71
- Reaction score
- 161
Problem with M&P 10mm + Customer Service Nightmare
- Thread starter mark_lives_things
- Start date
It seems like all the polymer 10mms are having some issues. Maybe some more than others.
I think it's the wide variety of bullet shapes and power levels that are giving manufacturers fits.
I don't think they are testing with a broad enough spectrum of ammo.
I think it's the wide variety of bullet shapes and power levels that are giving manufacturers fits.
I don't think they are testing with a broad enough spectrum of ammo.
mrshyvley
Member
45 ACP Mag Testing and Modifications
Since the 14rd extended .45acp mag proved promising, ended up getting a 10 round 45 ACP magazine to test with too. I wonder if I can get S&W to reimburse me for these
.
With the 45 ACP 10 round magazine, the max that I can load is 14 rounds of 10mm. This is to be expected with such aggressive ribs. S&W doesn't have to be that aggressive for 10mm, it just needs to start the channeling right below the mag catch cutout.
Interestingly enough the .40 S&W magazine has the IDENTICAL channeling rib design to the 10mm! I wonder if those guys have seen this issue with hotter .40 S&W hardcast loads too.
10mm vs 45 Mag Catch Protrusion
Now that I can get a similar inside picture, here is what the mag catch looks like in the 10mm mag and the 45 ACP mag. Top pic set is gravity pushing the mag closer to the catch and bottom set is gravity pulling away from the catch. There is a slight difference, but not significant enough.
10mm vs 45 Feed Lip Width
The biggest issue with .45 ACP mags is the feed lips are too far apart. This causes the 10mm rounds point too far up and will cause the rounds to get stuck in the roof of the chamber.
10mm Feed Lip Opening: 0.387in
45acp Feed Lip Opening: 0.414in
Modifying 45acp Magazine's Feed Lips
I used a set of needle-nose pliers and started bending in the feed lips as much as they would go, the goal is to get as close to the 0.387 as the factory 10mm magazine. This was a royal pain, the metal is strong and doesn't want to bend easily (which is actually a good thing for longevity!) After an hour or so I was able to get it to around 0.395, I wanted to go further but my tools are not sufficient sadly. I can't easily push the 10mm rounds up and pop them out anymore so it might be good enough.
Here is a comparison of the feed angles after smacking the mag in. 10mm vs 45 acp vs 45 acp modded:
Range Report
Please note testing was done with the 24lbs Glock 20 Recoil IWI recoil spring on factory guide rod.
Extended 14rd 45 ACP Mag MODIFIED
The modified 14 round 45 ACP magazine (extended) worn in a little and now seems to fit 20 rounds of 10mm! It cycled light 10mm loads to heavier Underwood JHP and DoubleTap Hardcast with 99% reliability*! No mag drops, perfect feeding and cycling even with rapid firing.
*I did have one slight failure to fully chamber halfway through that mag, but I had a mixture of hot and light loads in the same mag thus I can't dismiss limp wristing as the cause.
10 Round 45 ACP Unmodified
To my surprise this magazine cycled fairly reliably too. No mag drops, slow firing it seemed fairly reliable. With rapid firing the issues started showing up where the rounds would get stuck in the roof of the chamber. Not a big surprise with the factory feed lip spacing.
After wearing in the magazine I was able to fit 15 rounds but after I did the feed lip mod on this mag it went back to 14 rounds max sadly. Better to have 14 non-mag dropping rounds then 15 or even 30 rounders that will drop mags when you use them. It's easier to re-rack the slide then to fish for the magazine as a bear is charging at you.
I already modded this mag and it should be good to go like the 20 rounder. Biggest annoyance is not having accurate round count peep holes.
Factory 10mm Mag Update
I fired a good 15 rounds of DoubleTap 200gr hard cast rounds and didn't have a single issue, no mag drop no failures to feed. The 24lb spring AND bending the mag catch/release spring (which increases mag release spring tension) is still working well too.
Here is the Mag release spring, I bent it slightly in the opposite direction of the mag release travel. This provides extra spring tension on the mag release thus it withstands the bullet tips hitting it better.
Next Range Trip testing..
Since this has a fairly noticeable off center cant now, I swapped the mag release to be lefty. In theory the gun show now drop the mags since the mag release spring has less pre-load then even stock.
Since the 14rd extended .45acp mag proved promising, ended up getting a 10 round 45 ACP magazine to test with too. I wonder if I can get S&W to reimburse me for these
.With the 45 ACP 10 round magazine, the max that I can load is 14 rounds of 10mm. This is to be expected with such aggressive ribs. S&W doesn't have to be that aggressive for 10mm, it just needs to start the channeling right below the mag catch cutout.
Interestingly enough the .40 S&W magazine has the IDENTICAL channeling rib design to the 10mm! I wonder if those guys have seen this issue with hotter .40 S&W hardcast loads too.
10mm vs 45 Mag Catch Protrusion
Now that I can get a similar inside picture, here is what the mag catch looks like in the 10mm mag and the 45 ACP mag. Top pic set is gravity pushing the mag closer to the catch and bottom set is gravity pulling away from the catch. There is a slight difference, but not significant enough.
10mm vs 45 Feed Lip Width
The biggest issue with .45 ACP mags is the feed lips are too far apart. This causes the 10mm rounds point too far up and will cause the rounds to get stuck in the roof of the chamber.
10mm Feed Lip Opening: 0.387in
45acp Feed Lip Opening: 0.414in
Modifying 45acp Magazine's Feed Lips
I used a set of needle-nose pliers and started bending in the feed lips as much as they would go, the goal is to get as close to the 0.387 as the factory 10mm magazine. This was a royal pain, the metal is strong and doesn't want to bend easily (which is actually a good thing for longevity!) After an hour or so I was able to get it to around 0.395, I wanted to go further but my tools are not sufficient sadly. I can't easily push the 10mm rounds up and pop them out anymore so it might be good enough.
Here is a comparison of the feed angles after smacking the mag in. 10mm vs 45 acp vs 45 acp modded:
Range Report
Please note testing was done with the 24lbs Glock 20 Recoil IWI recoil spring on factory guide rod.
Extended 14rd 45 ACP Mag MODIFIED
The modified 14 round 45 ACP magazine (extended) worn in a little and now seems to fit 20 rounds of 10mm! It cycled light 10mm loads to heavier Underwood JHP and DoubleTap Hardcast with 99% reliability*! No mag drops, perfect feeding and cycling even with rapid firing.
*I did have one slight failure to fully chamber halfway through that mag, but I had a mixture of hot and light loads in the same mag thus I can't dismiss limp wristing as the cause.
10 Round 45 ACP Unmodified
To my surprise this magazine cycled fairly reliably too. No mag drops, slow firing it seemed fairly reliable. With rapid firing the issues started showing up where the rounds would get stuck in the roof of the chamber. Not a big surprise with the factory feed lip spacing.
After wearing in the magazine I was able to fit 15 rounds but after I did the feed lip mod on this mag it went back to 14 rounds max sadly. Better to have 14 non-mag dropping rounds then 15 or even 30 rounders that will drop mags when you use them. It's easier to re-rack the slide then to fish for the magazine as a bear is charging at you.
I already modded this mag and it should be good to go like the 20 rounder. Biggest annoyance is not having accurate round count peep holes.
Factory 10mm Mag Update
I fired a good 15 rounds of DoubleTap 200gr hard cast rounds and didn't have a single issue, no mag drop no failures to feed. The 24lb spring AND bending the mag catch/release spring (which increases mag release spring tension) is still working well too.
Here is the Mag release spring, I bent it slightly in the opposite direction of the mag release travel. This provides extra spring tension on the mag release thus it withstands the bullet tips hitting it better.
Next Range Trip testing..
Since this has a fairly noticeable off center cant now, I swapped the mag release to be lefty. In theory the gun show now drop the mags since the mag release spring has less pre-load then even stock.
Attachments
Last edited:
Excellent work @vram01k!
Seems we have this problem hemmed up. Now does anyone have direct contact with S&W R&D to forward this information to so they can fix the problem?
Of course if MecGar would make a magazine for this gun and incorporate this modification, we would be golden.
Thanks,
Rosewood
Seems we have this problem hemmed up. Now does anyone have direct contact with S&W R&D to forward this information to so they can fix the problem?
Of course if MecGar would make a magazine for this gun and incorporate this modification, we would be golden.
Thanks,
Rosewood
Since the 14rd extended .45acp mag proved promising, ended up getting a 10 round 45 ACP magazine to test with too. I wonder if I can get S&W to reimburse me for these
With the 45 ACP 10 round magazine, the max that I can load is 14 rounds of 10mm. This is to be expected with such aggressive ribs. S&W doesn't have to be that aggressive for 10mm, it just needs to start the channeling right below the mag catch cutout.
Interestingly enough the .40 S&W magazine has the IDENTICAL channeling rib design to the 10mm! I wonder if those guys have seen this issue with hotter .40 S&W hardcast loads too.
10mm vs 45 Mag Catch Protrusion
Now that I can get a similar inside picture, here is what the mag catch looks like in the 10mm mag and the 45 ACP mag. Top pic set is gravity pushing the mag closer to the catch and bottom set is gravity pulling away from the catch. There is a slight difference, but not significant enough.
10mm vs 45 Feed Lip Width
The biggest issue with .45 ACP mags is the feed lips are too far apart. This causes the 10mm rounds point too far up and will cause the rounds to get stuck in the roof of the chamber.
10mm Feed Lip Opening: 0.387in
45acp Feed Lip Opening: 0.414in
Modifying 45acp Magazine's Feed Lips
I used a set of needle-nose pliers and started bending in the feed lips as much as they would go, the goal is to get as close to the 0.387 as the factory 10mm magazine. This was a royal pain, the metal is strong and doesn't want to bend easily (which is actually a good thing for longevity!) After an hour or so I was able to get it to around 0.395, I wanted to go further but my tools are not sufficient sadly. I can't easily push the 10mm rounds up and pop them out anymore so it might be good enough.
Here is a comparison of the feed angles after smacking the mag in. 10mm vs 45 acp vs 45 acp modded:
Range Report
Please note testing was done with the 24lbs Glock 20 Recoil IWI recoil spring on factory guide rod.
Extended 14rd 45 ACP Mag MODIFIED
The modified 14 round 45 ACP magazine (extended) worn in a little and now seems to fit 20 rounds of 10mm! It cycled light 10mm loads to heavier Underwood JHP and DoubleTap Hardcast with 99% reliability! No mag drops, perfect feeding and cycling even with rapid firing.
I did have one slight failure to fully chamber halfway through that mag, but I had a mixture of hot and light loads in the same mag thus I can't dismiss limp wristing as the cause.
10 Round 45 ACP Unmodified
To my surprise this magazine cycled fairly reliably too. No mag drops, slow firing it seemed fairly reliable. With rapid firing the issues started showing up where the rounds would get stuck in the roof of the chamber. Not a big surprise with the factory feed lip spacing.
After wearing in the magazine I was able to fit 15 rounds but after I did the feed lip mod on this mag it went back to 14 rounds max sadly. Better to have 14 non-mag dropping rounds then 15 or even 30 rounders that will drop mags when you use them. It's easier to re-rack the slide then to fish for the magazine as a bear is charging at you.
I already modded this mag and it should be good to go like the 20 rounder. Biggest annoyance is not having accurate round count peep holes.
Factory 10mm Mag Update
I fired a good 15 rounds of DoubleTap 200gr hard cast rounds and didn't have a single issue, no mag drop no failures to feed. The 24lb spring AND bending the mag catch is still working well too.
I did this exact same mod to a couple of 45 magazines, but I need to put in some more time messing with the feed lips because mine are still not locking back on empty.
They do run with no hiccups or malfunctions with just not locking back being the only issue I have so far.
I also made a magazine feed lip tool a few years ago with an old Philips head that I cut the head off of and used a thin cut wheel on my Dremel tool and it works wonderfully. I specifically used a stubby Phillips head so there would be less torque when bending feed lips causing me to overdo it.
When you say you bent the mag catch, do you mean the mag catch hole on the magazine itself?
Attachments
Last edited:
Interesting, mine lock back no problem, I don't believe that's feed lip relate since the slide stop trigger on the magazine is way up front. It's possible that you over compressed the feed lips that the follower doesn't go up as high? But I highly doubt that since your tool is far more precise then what I did with my needle nose pliers.
That's a great idea, I'm gonna make one too with a spare tool/metal. That should help me finish bending the lips, otherwise I do get slight pop up if I really slam the mag in.
Updated the post to clarify that it's the mag catch/release spring.
Notice how it's slightly off center now? This provides an extra pre-load on the mag catch. In theory swapping it sides (to be lefty) will cause less preload then even factory, so it should be dropping mags very easily.
Yeah yeah we know.
Don't buy garbage pistols like you do, and learn from your mistake right?
I called MecGar, and asked if they would consider making a magazine of a different design. The rep on the phone flat out said "NO" -- no "ifs", no "buts", just flat "NO."
Since the 14rd extended .45acp mag proved promising, ended up getting a 10 round 45 ACP magazine to test with too. I wonder if I can get S&W to reimburse me for these
With the 45 ACP 10 round magazine, the max that I can load is 14 rounds of 10mm. This is to be expected with such aggressive ribs. S&W doesn't have to be that aggressive for 10mm, it just needs to start the channeling right below the mag catch cutout.
Interestingly enough the .40 S&W magazine has the IDENTICAL channeling rib design to the 10mm! I wonder if those guys have seen this issue with hotter .40 S&W hardcast loads too.
10mm vs 45 Mag Catch Protrusion
Now that I can get a similar inside picture, here is what the mag catch looks like in the 10mm mag and the 45 ACP mag. Top pic set is gravity pushing the mag closer to the catch and bottom set is gravity pulling away from the catch. There is a slight difference, but not significant enough.
10mm vs 45 Feed Lip Width
The biggest issue with .45 ACP mags is the feed lips are too far apart. This causes the 10mm rounds point too far up and will cause the rounds to get stuck in the roof of the chamber.
10mm Feed Lip Opening: 0.387in
45acp Feed Lip Opening: 0.414in
Modifying 45acp Magazine's Feed Lips
I used a set of needle-nose pliers and started bending in the feed lips as much as they would go, the goal is to get as close to the 0.387 as the factory 10mm magazine. This was a royal pain, the metal is strong and doesn't want to bend easily (which is actually a good thing for longevity!) After an hour or so I was able to get it to around 0.395, I wanted to go further but my tools are not sufficient sadly. I can't easily push the 10mm rounds up and pop them out anymore so it might be good enough.
Here is a comparison of the feed angles after smacking the mag in. 10mm vs 45 acp vs 45 acp modded:
Range Report
Please note testing was done with the 24lbs Glock 20 Recoil IWI recoil spring on factory guide rod.
Extended 14rd 45 ACP Mag MODIFIED
The modified 14 round 45 ACP magazine (extended) worn in a little and now seems to fit 20 rounds of 10mm! It cycled light 10mm loads to heavier Underwood JHP and DoubleTap Hardcast with 99% reliability*! No mag drops, perfect feeding and cycling even with rapid firing.
*I did have one slight failure to fully chamber halfway through that mag, but I had a mixture of hot and light loads in the same mag thus I can't dismiss limp wristing as the cause.
10 Round 45 ACP Unmodified
To my surprise this magazine cycled fairly reliably too. No mag drops, slow firing it seemed fairly reliable. With rapid firing the issues started showing up where the rounds would get stuck in the roof of the chamber. Not a big surprise with the factory feed lip spacing.
After wearing in the magazine I was able to fit 15 rounds but after I did the feed lip mod on this mag it went back to 14 rounds max sadly. Better to have 14 non-mag dropping rounds then 15 or even 30 rounders that will drop mags when you use them. It's easier to re-rack the slide then to fish for the magazine as a bear is charging at you.
I already modded this mag and it should be good to go like the 20 rounder. Biggest annoyance is not having accurate round count peep holes.
Factory 10mm Mag Update
I fired a good 15 rounds of DoubleTap 200gr hard cast rounds and didn't have a single issue, no mag drop no failures to feed. The 24lb spring AND bending the mag catch/release spring (which increases mag release spring tension) is still working well too.
Here is the Mag release spring, I bent it slightly in the opposite direction of the mag release travel. This provides extra spring tension on the mag release thus it withstands the bullet tips hitting it better.
Next Range Trip testing..
Since this has a fairly noticeable off center cant now, I swapped the mag release to be lefty. In theory the gun show now drop the mags since the mag release spring has less pre-load then even stock.
Truly wonderful work and perseverance! I've just placed an order for a 10-rd mag and will report how it goes for me.
I'd say this is not likely to happen with the 45 ACP mag. In theory, since the bullet tips are sufficiently far away from the catch, it should retain the magazine at just about any retention spring stiffness.
That being said, the "sufficiently far away" is key here.
I tried filing the mag catch (I got one from Galloway for experimentation), and even though I could minimize the protrusion of the reverse side of the mag catch, the mag would still drop when using hot loads.
Eventually, I filed the mag catch too much, and the mag would drop even when a round was chambered.
This experiment (along with the need for a stiffer recoils spring) confirms the triple nature of this problem.
First, the magazine has very poor design that allows rounds to come flush against the mag catch window. This is the driver of the issue.
Second, some bullets are just large enough to fill that window perfectly and thus exert pressure on the mag catch.
Third, if the powder load is sufficient, the shot jolt might make the bullet press on the mag catch just enough to cause ejection.
Conclusion 1:
If you don't have any contact between the bullet and the mag catch, the powder load should make no difference.
Evidence:
None of the jacketed Underwood ammo (I tested almost the entire range) caused the mag drops.
Conclusion 2:
Conversely, if you do have contact between the bullet and the mag catch, the combination of the powder load, mag catch spring, and recoil spring matter.
Evidence:
With the stock spring S&B 180 gr JHP would cause mag drops (those JHPs are just as large as Underwood hardcast bullets). The problem goes away with the 22lb recoil spring.
Top O' Texas
Member
Fortunately, I've hadn't had any issues with the 2.0 10mil I have. 4" w/manual safety and 200 rounds total with ppu and armscor. No reloads as of yet. I bought this as of passing on the x-ten with safety issues.
All mag drop issues with this pistol arise when (1) spicy ammo with (2) wide-tipped bullets is used, so neither PPU nor Armscor fit the description.
Factory 10mm Mag Update
I fired a good 15 rounds of DoubleTap 200gr hard cast rounds and didn't have a single issue, no mag drop no failures to feed. The 24lb spring AND bending the mag catch/release spring (which increases mag release spring tension) is still working well too.
Here is the Mag release spring, I bent it slightly in the opposite direction of the mag release travel. This provides extra spring tension on the mag release thus it withstands the bullet tips hitting it better.
Next Range Trip testing..
Since this has a fairly noticeable off center cant now, I swapped the mag release to be lefty. In theory the gun show now drop the mags since the mag release spring has less pre-load then even stock.
It's been a minute, but I finally got a chance to test this out and the results are not quite what I expected. Keep in mind all this testing was done with a 24lb Glock 20 recoil spring.
Left Handed Mag Release
With the mag release being setup for left handed operation, the 10mm magazine dropped a single time shooting spicy Hardcast Underwood 220gr (old style wider bullet, back before they were coated and used silver shells). I also had two high feed failures, one on 10mm magazine and one on .45 acp magazine, those 220 grain rounds were a mule though. I believe the very short 10mm feed lips are to blame for this, while .45 acp lips are wider because I plier bent them the front edges don't really snugly hold the bullets. I need to do the dremel screw driver bender Gman556 mentioned here.
Right Handed Mag Release
I then swapped the mag release back to right hand operation and continued to test, I then had multiple mag drop events with the same ammo! This is opposite of what I expected, I expected the left handed side to drop the mags more since the mag release spring was preloaded for right handed operation.
Rebending the Mag Release Spring
Finally, I once again pre-bent/pre-loaded the mag release spring and then I had ZERO mag drops, at this point I was running out of 220gr but I fed 200gr Double Tap and the new 200gr Underwoods. This once again points me to the mag release spring being too weak for this magazine design.
All of the hard cast bullets that I checked had gashes on them from the mag catch hitting them.
Testing .40 SW Rounds
I also fired a bunch of .40 S&W random hollow points without a problem, all cycled well with 24lb spring!
Conclusion - Smith & Wesson To do list
Smith & Wesson, we did all the R&D and work for you please...
- Increase the recoil spring to 24lb, even with such a heavy recoil spring the spicy rounds get yeeted 10-20ft away!
- Redesign the 10mm magazine to channel the bullets before mag catch window, similar to the .45 magazine.
- (Not needed if you redesign the 10mm Mags) Increase the mag drop spring weight, so that it doesn't release as easily with current 10mm magazines.
Last edited:
This for sure proves the hypothesis. If the mag catch is leaving marks on the boolits, that is definitive proof the boolit is hitting the catch and the reason for the drop.
Now if S&W will listen.
Anyone on here have an inside connection to S&W R&D that they can reach out and provide the results?
I am not sure how the manufacture the mags, but wonder if they use some sort of die to shape them. Could they modify their die then run a customer's mag through it to extend that groove in the mag to keep the boolit off the catch? Probably gonna cost them a pretty penny, but methinks a recall is in order or replacement mags one.
Rosewood
Last edited:
I've been trying to make the issue as concise as possible, and here's what I have so far.
- The issue:
The channeling ribs of the magazine are too short. - Universal manifestations of the issue in 4 pictures:
- Large (200gr+) hardcast bullet is flush with the catch window.
- The catch is protruding far enough into the mag.
- The catch is resting on the bullet of round #11 (counting from the bottom of the mag) to the point of measurably pushing the back of the mag release by 1/16".
- Catch leaves deep gauges on round #11 when the gun is fired.
- The contact between the mag catch and the bullet MAY lead to the ultimate failure: magazine drop.
- The mag catch spring stiffness likely determines whether the ultimate failure occurs.
- I believe, EVERYONE who owns S&W M&P 10mm HAS THIS PROBLEM, however...
- Most people do not fire spicy ammo with hardcast bullets.
- Ultimate failure (mag drop) may manifest inconsistently primarily due to the mag catch spring stiffness.
Last edited:
It's been a minute for me a as well
I have encountered a completely bizarre counter-issue: my mags stopped dropping EVEN with the stock recoil spring and Underwood 220gr hardcast rounds!
After much deliberation, I believe it is due to the fact that I inadvertently bent the mag catch spring just a bit -- similar to what you did. I replaced mag catches from original to Springer Precision (and filed the latter down several times).
This really confirms the suspicion that EVERYONE who owns the M&P 10mm has this issue -- that's just physics -- but most people do not fire spicy hardcast rounds and/or have stronger mag catch springs.
I think we've explored this issue completely and explained all variables.
Please read at least some of the replies in this thread. You are way off with your suggestion.
TL;DR: This problem is a result of a poor magazine design.
Another issue the 45ACP mag fixes: FTFs.
I have also discovered another problem with the 10mm magazine: feed lips are too short.
I need to write this all up properly...
I have also discovered another problem with the 10mm magazine: feed lips are too short.
- A number of people reported FTFs with various rounds, including typical range ammo.
- Curiously, I personally experienced multiple FTFs with the 40SW. Yes, I'm aware that the gun is not designed for it, but that's besides the point, as in general all 10mm guns shoot 40SW just fine.
I need to write this all up properly...
Similar threads
