Finally got a 4" 10mm MP this Friday. Took it to the range Saturday morning.
First of all, love how it shoots compared to my XDMs, like the trigger way more. What started happening I don't like so much. Never encountered this before so I don't even know where to start to address it other than calling Smith and Wesson. Maybe the hive mind here might have some answers.
I used Magtech 180gr 10mm which is reasonably hot and Hornady critical duty for this range session. Unfortunately about 25% of the time, the pistol will spit the last live round out the top and lock the slide back. It did with with both types of ammo, one mag seemed to do it more than the other but I didn't really try to test this too much because I was loosing live rounds down the range and didn't want to force everyone to stop shooting to retrieve them so I just started pulling the mag and reloading when the second to last round was chambered.
I will take it to the grasslands and put a bunch through it with 3-4 rounds in the mag each time and with the go pro recording in slow mo to see if I can catch what exactly is happening. These MP 10mm mags do seem to have very short feed lips on them compared to even my 45c. I have pretty much every other type of failure to feed, but this one is totally new to me. Tried to find some details online, but I can only find some references to some sig sauers doing it years ago.
I also need to do something about the grip on this thing. People must have gotten it into companies minds that they expect to have to use a pistol after having to dip their hands in gear lube. The stippling on this thing is way way over the top. Short of putting a rubber sleeve on it any un-stippling methods around that don't look terrible on the finished product? I haven't once grabbed my 45c and thought dang man this thing is just too slick I need to glue some sandpaper to it but anymore thats the entire MP line.
Aside from tossing the last round unfired out the top, and the meat grinder grip. I love this thing. I will be keeping an eye out for the 4.6" to permanently attach an optic to. I'll also be installing standard night sights on my 4". The "optic height" sights from the factory don't clear a fast fire 3 anyway.
For the grip issue, you could always throw on Tallon grips. I have them on several of my pistols and really like them.
My solution to overly agressive grip texture on a polymer gun is sandpaper. Just rub some 220 grit on the grip until you knock enough edges off to be the right amount of grippy.
Quote from: sqlbullet on April 11 2022 08:07:53 AM MDT
My solution to overly agressive grip texture on a polymer gun is sandpaper. Just rub some 220 grit on the grip until you knock enough edges off to be the right amount of grippy.
That'll definitely work.
I bought an gen 1 palmswell from Midwest Gun Works for mine. It was under $6. The texture of the front and sides makes for a good grip on the gun without chewing into the web between my thumb and forefinger.
The last round ejection situation is unfortunate. I specifically ran my 4" M&P 10 with different power level and length rounds to test the reliability and didn't have a single bobble. Sorry to hear that there's a problem with yours. It makes me wonder if there was an issue with magazine production. Perhaps that explains why there are no spare mags available yet. Maybe some faulty ones got out into the world.
In working up a load and testing my Kimber 1911 with the 10MM barrel I fit to it I had the issue of last round popping out of the magazine and the slide locking back with full power 180 grain loads.
After I upped the recoil spring to 22 Lbs it never happened again. My guess is the slide was slamming back against the slide stop too hard from the lighter recoil spring and causing the last cartridge to move forward relative to the pistol and popping out of the magazine. Never happened again once I upped the recoil spring.
The last round popping out is your mag pushing up the last round before the slide can catch it. I had a 1911 45 that would due the same thing. To fix it I left the mags loaded for a couple weeks
I had a Gen3 G23 that did this but only with one of the (10rd) mags it came with. Bought it during the Ass Ban, can you believe that - a "Blue Label" had to be sold with 10rd mags?!?! Those were strange days. Anyway-i would load 10rd, when I shot #9, the slide would lock back as #10 was ejected LIVE out like a piece of spent brass. Dumped the mag (we were past "sunset" anyway) and it never happened again. My guess - bad/weak lips.
On a side note, let us know how that M&P handles BB and UW, if you put any through it. Thanks.
I'd try this:
Quote from: bigboredad on April 18 2022 09:39:01 PM MDT
The last round popping out is your mag pushing up the last round before the slide can catch it. I had a 1911 45 that would due the same thing. To fix it I left the mags loaded for a couple weeks
As a followup to this...
Went to the grasslands and put a mess of rounds through it. First it was doing the same thing on both mags randomly would spit the last live round out of the top and lock the slide back. As best I could tell from slow motion on the go pro, its a combination of things.
1: The mag spring is weak. Thought this might be the issue given it takes less to put the 15th round into my MP than the first couple in my XDM.
2: The mag lips are wildly short compared to other 10mm firearms and even MP other calibers.
So watching the slow motion on the couple instances I managed to capture, the round was not pressed up against the lips before the slide battered back and started really racking the whole frame back. Inertia took effect and the round stays where it was when the frame starts coming back. By the time the spring in the mag catches up and starts pushing the round up against the lips, the round has cleared 50% or more of the lips. Once the spring has finally caught up and the slid is just starting to go forward the follower has shot the last round out of the mag and locked the slide back.
So as a temp test fix, I disassembled 1 mag and stretched the springs out as far as I dared. Put it back together and re-ran it. The mag with the stretched spring ran wonderfully, the original one still occasionally popped out the last round. Of course stretched springs only work so long before they go back to normal rate, so Ill be keeping an eye out for a wolf mag spring with significantly more force.
Also had one new failure, round nosed up and wedged between slide and barrel. In my limited 1911 10mm experience, this was also resolved by a stiffer mag spring.
All signs point to a couple new heavier springs to address most of the issues I experienced.
As a solid good side to the trip, once I got the red dot dialed, it had a super nice grouping. Soda Cans at 50 yards didn't stand a chance.
I tried the XD-M and didn't like the grip on it. Our XD has always felt good in the hand! They should have built it on that IMO.
I have been having the same "loaded round ejection" problem with my 4.6" gun, as well as it seems to like feeding the odd round into the barrel hood instead of the chamber. I installed a Wolff guide rod and 24 pound spring and it helped, but didn't completely resolve the problem. I installed a Wolff extra power magazine spring in one of the mags and that cut down the failure rate a little bit also... Today I was out at the LGS and they had 10mm magazines, so I snagged one. Once I got home I took it and the other stock magazine apart to compare them. This is what I found: (http://bearsears.org/10mm%20springs.jpg)
The old spring is at the top, the one out of the new magazine on the bottom. Neither one of these magazines had been disassembled before. See the problem on the older mag spring follower? So now I'm wondering if anyone else has checked this on their malfunctioning guns and found that the follower was installed backwards at the factory and if that could be a cause of all of our feeding problems with these guns. I haven't had a chance to run out to the range and test the theory myself yet.
Sounds like someone?s first day on the job. Did you happen to to contact their Customer service about your find?
For some reason the 4" seem to be more troublesome than the 4.6. I have 6 magazines for my 4.6 no issues at all. I have 750 rounds down range so far. My target load is 165 grain polymer RNFP with 4.7 grains of 231. I did replace the captive recoil spring with a Wolff guide rod and heavier spring.
Funny, I had the same issue with some Pro Mags (low quality) for a Ruger PC40 many years ago.Purchased three mags, two worked great and third one was a problem child. Finally I realized they had assembled the follower backwards on the problem mag. Reversed it and problem solved. I just didn?t use that mag for a few years until it occurred to me . If you ever have this problem, then you will always think of this possibility. Nice job realizing this snafu.
Andy
So yesterday I took the new magazine out to the range. It did seem to perform better, but still not 100%. I also installed a +10 Wolff .45ACP spring in one of the other magazines. Didn't seem to make much difference. Still getting these stupid failure to feed malfunctions, but hey, at least this time it only puked one loaded round out of the gun! I don't understand this, as it runs my standard .40 S&W load fine, with no problems. Which is stupid, because if I wanted another .40, I would have bought one. Attached are pictures of the malfunctions I encountered while running some book safe, but honest 200gr lead flat points at a chronographed average of 1200fps. Still looks like the slide is outrunning the magazine spring. Still using the 24lb. Wolff recoil spring.
Bolt over base malfunction. Either your slide needs to slow down or your magazine needs to speed up. I would suggest a stronger recoil spring next.
Totally agree with Sqlbullet, regarding the slide outrunning the magazine. I'd also take a look at your barrel fit. Recoil spring and barrel fit will determine the lock time on an M&P. Take a look at this if you're not familiar on proper barrel fit. https://www.youtube.com/watch?v=QqCu1jnVwZ4
Good luck with it. Sorry you're having such a problem with yours. My 4" M&P 10 runs like a champ. Hopefully yours will too when you get it figured out.
The pic Weldmeister posted above with the old and new mag spring and follower... Notice the difference in the spring length. I have a 4.6" model I bought on 12/16/21 (manf date on the box is 12/7/21) so its one of the first off the line models. Have not has any issues with it from shooting soft S&B FMJ, (hot) Hornady Custom XTPs, to nuclear Federal HSTs.
It doesn't really eject the brass to the other side of the county like my custom 1911 10mm does either. Even with the hot HSTs rounds. You need to bring the bushhog to retrieve the ejected brass from my 1911. And make sure nobody is standing to your right side also even with a FFP stop, increased main spring, and 22# recoil spring.
Both factory mags that came with the 4.6" gun in December have mag springs that measure 6" long brand new the day I bought it. I always measure mag spring length and record it for my own personal database of info.
Approximetly 1 month ago my local shop got in the first batch of 10mm mags for sale and I recieved a text saying they were in. I bought 2 of them that day and tore them apart and measured them that day. The S&W brand replacement mags had springs in them that measured 7" long now!! That is 1" longer that the mag springs that came with the pistol. Wire diameter and coil count remain the same.
I bought some Wolff 45 springs to measure them for reference and they measure 6" OAL length. Wire diameter tha same and 1 less large coil on bottom. So even putting 45 springs in there probably isn't going to gain you anything.
But in any event even though you can feel a definite difference when pushing down on the follower between the old 6" and new 7" long springs, I have not had any issues with either sets of mags yet in my gun. So jsut an FYI:
Steve
So I found this today on YouTube about the possible issues I am having with this gun, and as most of you have said, it is related to weak magazine springs. Worth the watch if you are having this problem. I ordered a set of Springer Precision Magazine Springs today. Will report. Greybreard, I did check out the barrel fit as per the information you supplied. No problems there. This pistol is not going to win. It will function, just gotta get it sorted out.
https://www.youtube.com/watch?v=DXb8_MNLvPk
Just to circle back around to this, stretching the mag springs on mine resolved my issues. I haven't had a failure in a couple hundred rounds with either mag that it came with.
Maybe we will get a 10mm with the new metal frame in the future. Probably not but I can wish.
So... Got the Apex extractor and installed it today. Took the M&P out to the range and tried it out... I gotta say... This part has cured my problem! I only ran 100 rounds through it, but had zero problems. And this was with full power, 200gr bullet at 1200 fps loads. I will keep monitoring it, but I have to say thanks to Apex for helping me get this thing reliable. I played with magazine springs, recoil springs and everything else, but before I installed the Apex extractor, I couldn't get through one magazine without failures to feed, failures to eject and loaded rounds puking out of the ejection port. Today's test was with the stock magazine springs, and the 24lb recoil spring.
This fix was suggested on a FB M&P page. The explanation I got I will paste below from Scott Folk at Apex:
Scott Folk:
"Most people don't realize that the extractor in a pistol is integral to the feeding process. The stripper rail picks up the top edge of the brass to advance it forward out of the mag. As the bullet rides up the feed ramp, the rim of the cartridge slides up against the breech face, but not flat against, the bottom edge is away from the breech while the top is against the breech. The extractor has to be cammed out by the case rim against spring tension. There is a necessary feeding cut on the bottom of the extractor that helps cam the extractor out, we call it the feeding cut. What we found on the m&p extractors is that the feeding cut angle is not optimal and often creates too much tension against the case. In the case of a 10mm, due to the radius of the cartridge and speed of feeding, often the case jams against the entry cut causing a feeding malfunction, or the extractor can't cam out which causes the brass to pop off the breech face.
At Apex, we happened to receive 2 10mm that wouldn't feed for Jack. I did some experimenting and determined that the pistol would feed cleanly without an extractor, which meant that the extractor was the cause. We did some magic Apex Voodoo that we do and we're able to create optimized feeding geometry.
When the original m&p launched, mine had terrible extraction, it was so bad that in a uspsa match, my long rotating transition was fast enough that I caught a piece of brass on top of my slide between shots. This caused us to redesign the original m&p extractor and call it our Failure Resistant Extractor or FRE. We applied a similar technique to the Glock gen 3 extractors and were able to drastically improve the ejection pattern of the G3 platform.
All this is to say that we've been doing this a long time and we've gotten pretty good at fixing feeding and extraction issues at Apex."