New M&P15 with feeding issue?

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Wombatz

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I put a question mark on that since this might just be a new gun needing better cleaning...

Brand new Smith & Wesson M&P15 Sport II
SKU: 10202

I am totally new to the AR-15. On sale at $499.99 I could not pass it up tho.

It has only 141 rounds thru it so far in two shooting/testing sessions.

The trouble is with rounds not fully feeding and getting damaged on the way to the chamber. This deforms the round as shown below and stops them feeding all the way into the chamber. At the worst it is every 5 rounds or so.

I did a basic field strip, clean and lube before the first trip but it was a pretty quick cleaning and mostly just learning about the parts since the platform is new to me.

After that I did more reading and did a bit more cleaning and tried to make it properly "wet" for the second trip out. At very first it was just as bad as before but this time I switched mags as soon as there was a misfire. I have two mags, one came with the gun and the seconds is the identical, so both are "PMAG30 AR/M4". The feeding trouble was the same for both mags.

But then I continued to fire and the trouble seems to have gone away, in that I was able to finish up firing all rounds in both mags without any more issues. So it was as if that "wet" condition took about 12 rounds before the oil got everywhere.


But maybe some pictures of the damage to the rounds will let somebody know exactly what is going on. I have 10 pictures hosted at:

http://wombatz.com/hosted/2019-07-03

If you click on a thumbnail it will give you the full size image.

Also adding one of the best pictures on this post.

P.S. I will now do a much longer full cleaning in case the problem is due to packing grease or whatever you call it.
 

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Ok so some questions and some things to do for diagnosis.

1. I assume these are new magazines? And you loaded them to 30 rounds?
2. Does your problem occur if you put your magazine in with the Bolt carrier group (BCG) in the locked back position and you release it with the bolt release? Or is it after firing the first round and is a failure to load the second round?
3. Does the rear end of the cartridge get stuck in the mag and the bolt impacts the neck area of the cartridge? Or does the cartridge slip out of the bolt and and the rear section of the cartridge get pinned above the bolt (this is called “brass over bolt” malfunction)?

I run my BCG wet, along with the “tail” of the bolt. It is also prudent to take the buffer spring out and put a light coat of oil on it as well. After this there are things I do with a new AR is to place one round in a magazine with the bolt in the catch, release the bolt and verify it is chambered and fire the round, the bolt should lock back. I repeat this several times to make sure the gas system, magazine, buffer and catch are all doing what they are supposed to.

It sounds like you have it running now that you’ve cycled the mag (new mags can have some issues) and lubed up the BCG.

It could be that your gas port is on the marginal size, or your gas key on your BCG is loose or gas block is leaking some of the gas, those can cause the BCG not to cycle fully and cause feeding issues. But if it continues to work itself out , just keep shooting it, and keep the BCG lubed and I bet it will settle itself out.

A good thing to diagnose problems with magazines is to not fully load them to capacity, put 27-28 rounds in the 30’s and see if that clears some problems up, some magazines need some cycling before being 100%.
 
Also, PMAG plastic feed lips are prone to warpage if the magazine is left fully loaded without the snap-on covers in place for any amount of time, espescially in a hot environment. The covers keep out dirt, but also take spring pressure off the feed lips.

Its entirely possible that the lips were pushed out when you first started shooting and have now returned to their original dimensions, thus resolving the problem.

I would try some new metal mags too, such as those from Brownells or C-Products, betcha the problem goes away.
 
Thank you both, very much. I will reply to both here...

Yes, these are new mags, and I have been filling them to 30 at home before heading to the forest. On the first trip I thing I might have had them loaded up the night before.

This *mostly* only happens after firing a round, so not when I am loading the first round. I have been inserting the mag and then pulling back the charging handle, being careful not to ride it. I added the "mostly" since I cycled fully thru both mags after I got home from the first outing. I used the handle to load a round and then pulled it 29 more times to cycle the rounds in and out. That test did have a few failures to fully chamber at first, but then it was running better as that test completed.

For question 3 I guess it seems that it is neither. When it fails to fire I find it almost in battery and the extractor is properly engaged. I am able to extract the round by pulling back on the handle. If I try the forward assist before extracting I can feel that it does not really want to fully seat and that makes sense since the rounds have some damage near the shoulder.

I am pretty sure that the bolt has held open after the last shot as each mag has been emptied, but next trip I will do a bunch of single round tests with each mag to make sure that it is holding open with both mags.

I will stop fully loading the mags as my testing continues. I will also take pictures *before* removing the rounds if this continues.

I am ok with getting a pair of metal mags if they are likely to be more reliable but I liked the idea of using what S&W provided, but this *is* an entry level gun and maybe they did not use the best mags. I was tending to trust the Magpul since Hickok45 had noted them as being well liked.

I have found the C Products 30 rounders at CheaperThanDirt and also found the ones that Brownells makes. I might just order a pair from one or the other.

P.S. I forgot to note the ammo I was using. This is Frontier .223 55grain Hollow Point Match. They come out pretty hot, so I don't suspect they are the issue but they are *not* actual 5.56. I will be getting some 5.56 in the next few days so will add that to the break in testing. If this *is* just break in issue than maybe the hotter 5.56 would have worked better.
 
Thank you both, very much. I will reply to both here...

Yes, these are new mags, and I have been filling them to 30 at home before heading to the forest. On the first trip I thing I might have had them loaded up the night before.

This *mostly* only happens after firing a round, so not when I am loading the first round. I have been inserting the mag and then pulling back the charging handle, being careful not to ride it. I added the "mostly" since I cycled fully thru both mags after I got home from the first outing. I used the handle to load a round and then pulled it 29 more times to cycle the rounds in and out. That test did have a few failures to fully chamber at first, but then it was running better as that test completed.

For question 3 I guess it seems that it is neither. When it fails to fire I find it almost in battery and the extractor is properly engaged. I am able to extract the round by pulling back on the handle. If I try the forward assist before extracting I can feel that it does not really want to fully seat and that makes sense since the rounds have some damage near the shoulder.

I am pretty sure that the bolt has held open after the last shot as each mag has been emptied, but next trip I will do a bunch of single round tests with each mag to make sure that it is holding open with both mags.

I will stop fully loading the mags as my testing continues. I will also take pictures *before* removing the rounds if this continues.

I am ok with getting a pair of metal mags if they are likely to be more reliable but I liked the idea of using what S&W provided, but this *is* an entry level gun and maybe they did not use the best mags. I was tending to trust the Magpul since Hickok45 had noted them as being well liked.

I have found the C Products 30 rounders at CheaperThanDirt and also found the ones that Brownells makes. I might just order a pair from one or the other.

P.S. I forgot to note the ammo I was using. This is Frontier .223 55grain Hollow Point Match. They come out pretty hot, so I don't suspect they are the issue but they are *not* actual 5.56. I will be getting some 5.56 in the next few days so will add that to the break in testing. If this *is* just break in issue than maybe the hotter 5.56 would have worked better.

I would try testing for lockback with one round in the magazine for a few times and then try downgrading your PMags to 25 or so in the magazine and see if you have the issue. And yes, pictures of the failure before rectifying it would help in determining the issue. Also, pay attention to the ejection pattern when you get it running, if the rifle is pointed at 12:00 where are the rounds ejecting? PMags have a good reputation for working and working well, but getting a metal magazine to try isn't a bad idea, I just think that it's something else causing the issue, based on the fact that you have two new PMags having the same issue.

I always like to get some M193 spec'd ammo for initial break-in just due to the fact it's loaded hot and provides adequate pressures for the initial run. And when you get it lubed up (BCG "wet" and buffer spring with a light coat of oil) and running, running a few magazines full through it, I bet it starts to work fine. Everyone's definition of "wet" on the BCG is different, I take my BCG out and take a squeeze bottle of oil and coat run a few lines down the side of the carrier and spread it out with my finger coating the whole carrier, and then put a drop or two on the tail of the bolt sticking out of the carrier and spread it around. Avoid any oil on the breech face.

The M&P Sports have a pretty good reputation of being a reliable, budget friendly AR. Solving AR cycling issues is a good process to go through for an owner, as it gets one familiar with how the platform works and will pay dividends in the future in keeping it running and understanding malfunctions when they occur with your own AR's or friends. It will also help you when you buy your second, and third AR :).

But if you continue to have problems and run out of patience, send it back to S&W and they'll take care of it for you.
 
Magpull mags are good ones, and are coming to be the standard ones manufacturers supply with their guns. That doesn't mean they can't go wrong, or have defects.
The suggestion to get some good metal ones and try those seems well founded in a way. If metal ones work, your rifle may just not like Magpuls for some reason.
Tracking down the reason for your weapon's problems sounds tricky; I don't usually like to offer opinions on guns I can't examine myself unless the problem is really obvious, and this one unfortunatly is not.
 
One thing about anodized aluminum is that it will take in oil. One will notice that when you take cleaner to anodized parts it dries out the surface and turns it white, oil brings it back to it's color. So on an initial outing with AR's I'm sure a lot of the oil is being pulled into the new, unoiled, dry aluminum surface. Hence, why you said it started running better once it was sufficiently wet and the oil got spread through the upper receiver race for the BCG.
 
Thank you both, very much. I will reply to both here...

Yes, these are new mags, and I have been filling them to 30 at home before heading to the forest. On the first trip I thing I might have had them loaded up the night before.

This *mostly* only happens after firing a round, so not when I am loading the first round. I have been inserting the mag and then pulling back the charging handle, being careful not to ride it. I added the "mostly" since I cycled fully thru both mags after I got home from the first outing. I used the handle to load a round and then pulled it 29 more times to cycle the rounds in and out. That test did have a few failures to fully chamber at first, but then it was running better as that test completed.

For question 3 I guess it seems that it is neither. When it fails to fire I find it almost in battery and the extractor is properly engaged. I am able to extract the round by pulling back on the handle. If I try the forward assist before extracting I can feel that it does not really want to fully seat and that makes sense since the rounds have some damage near the shoulder.

I am pretty sure that the bolt has held open after the last shot as each mag has been emptied, but next trip I will do a bunch of single round tests with each mag to make sure that it is holding open with both mags.

I will stop fully loading the mags as my testing continues. I will also take pictures *before* removing the rounds if this continues.

I am ok with getting a pair of metal mags if they are likely to be more reliable but I liked the idea of using what S&W provided, but this *is* an entry level gun and maybe they did not use the best mags. I was tending to trust the Magpul since Hickok45 had noted them as being well liked.

I have found the C Products 30 rounders at CheaperThanDirt and also found the ones that Brownells makes. I might just order a pair from one or the other.

P.S. I forgot to note the ammo I was using. This is Frontier .223 55grain Hollow Point Match. They come out pretty hot, so I don't suspect they are the issue but they are *not* actual 5.56. I will be getting some 5.56 in the next few days so will add that to the break in testing. If this *is* just break in issue than maybe the hotter 5.56 would have worked better.
Magpull mags are good ones, and are coming to be the standard ones manufacturers supply with their guns. That doesn't mean they can't go wrong, or have defects.
The suggestion to get some good metal ones and try those seems well founded in a way. If metal ones work, your rifle may just not like Magpuls for some reason.
Tracking down the reason for your weapon's problems sounds tricky; I don't usually like to offer opinions on guns I can't examine myself unless the problem is really obvious, and this one unfortunatly is not.
PMAGS have a reputation for reliability, indeed they are now USMC standard, but the covers are provided and designed that way for a reason. Lancer makes polymer mags with metal feed lips to avoid this issue.

I do have tons of PMAGs, but I usually keep my metal mags loaded as ready ammo and only load up the PMAGs just before usage.
 
Ok, it does sound like I should hold off my next trip out until I get the true 5.56 ammo.

The ejection pattern has been pretty tight, about 6 feet forward and right, maybe 45 degrees. I will be reloading so I was collecting the empties, after first cleaning up all the other 223 empties since this is popular shooting spot in the forest near home. I will measure it out more carefully on my next trip.

Again, thank you all very much for the support. As to my *next* AR; if I do really get into this then I suspect I will try a build from kits. I moved to Oregon from California, so I had not considered the AR before since California is crazy.

Oh, and I do have a chronometer so I guess I should take it on my next trip and check the speed of the .223 vs the 5.56 to get a better read on the ammo I am using.
 
When you say it’s ejecting forward and right are we talking 1:00, 1:30, 2:00, 2:30, etc?

Anything forward of 3:00 on ejection means that you are overgassed. If that’s the case I would try buying a heavier buffer to get your ejection pattern between 3:00-4:30. A heavier buffer doesn’t cost much and it’s nice to have a couple of different weights for troubleshooting in the future.

Other options for correcting overgassed rifles (add weight to the reciprocating mass or restrict gas flow) are:

1. Switching to an M16 carrier (if your carrier is a lightweight carrier)
2. Heavier Recoil spring
3. Adjustable gas block
4. Heavier buffer

Based on your ejection pattern you are not dealing with a gas leak, or undergassed causing short stroking.

Do you know how to remove your buffer? If not, I can help talk you through it. If so, can you take it out of the rifle and weigh it? I don't know what buffer S&W puts in those. If it was me I would go up in buffer weight and order the next size heavier or maybe two heavier (depending on ejection pattern). You shouldn't have to do this being it's a new rifle, and you can just send it back to S&W, but if you're like me I like to rectify problems myself if it's not too costly as I gain in understanding that way.

Disregard a lot of the buffers below the main ones you should concern yourself with are: Standard, H, H2, H3. If S&W puts the standard weight buffer in their Sport II's then a H or H2 would likely be what you need. And if one is going to get into AR's its nice to have all the buffers to swap around in determining any issues with future AR's.

Buffer%20Weights.jpg
 
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About 1:30, but clearly *not* 3:00 - 4:30. I had not read anything about that yet. I will start reading about the issue and all of the suggested fixes. Thanks much.
 
You should expect your rifle to shoot any .223, 556 ammo; I just prefer to start with m193 NATO spec ammo just for consistency and pressure sake with a new rifle.
 
Your brass dings, could be from the overgassing causing excessive recoil which can get the second round to slip up out of the magazine causing the bolt to hit it on the way to chambering a round. This can be a common problem in overgassed situations, solved by what I suggested above. But like you said, do some research for yourself and be the wiser for it. It's hard to diagnose over the internet, but once you get familiar with the AR the malfunctions can become easier to spot and diagnose.

In diagnosing AR's things to always watch to clue one in on problems are:

1. Ejection Patterns
2. What does the bolt and cartridges look like when malfunctioned
3. Recoil feeling (harsh or soft)
4. Malfunction type: FTF, FTL, FTE
 
Based on your ejection pattern I would anticipate your rifle to pass the "lock back on last round" test.
 
Weighed the buffer, and yup, a 2.9oz standard. It is a shame that we can't just put some lead shot in there to add weight.

I know. There are companies that make adjustable buffers with different combination of weights, I've never used one but can see that it would be really handy in solving issues.
https://www.odinworks.com/Adjustable_Buffer_p/os-abs.htm

I've always just had the different buffers to try out so I've never bought one; I've also moved on to adjustable gas blocks on nearly all my AR's except for my HD carbine.
 
Just seeing anybody say that was enough to get me to call. I briefly noted the issue and asked if it is likely to just be due to needing to be broken in. She did not think they needed it but put me on hold and checked. She came back pretty quick and said that yes, about 500 rounds is expected for break in. Not sure if they were just blowing me off or not.

My question to the group...

While researching this I have read that it is common to "over gas" the AR-15 and that seems to be the case for mine since it throws brass to about "1:30". I have ordered the adjustable buffer to try to tune it to a "3:00-4:30" brass throw. So, does it seem likely that the current "over gassed" situation is at least partly the cause of the feeding issue?

Note that I don't shoot at a range, so I don't care that it puts the brass forward of the "firing line". I just want to to chamber 100% of time.
 
Just seeing anybody say that was enough to get me to call. I briefly noted the issue and asked if it is likely to just be due to needing to be broken in. She did not think they needed it but put me on hold and checked. She came back pretty quick and said that yes, about 500 rounds is expected for break in. Not sure if they were just blowing me off or not.

My question to the group...

While researching this I have read that it is common to "over gas" the AR-15 and that seems to be the case for mine since it throws brass to about "1:30". I have ordered the adjustable buffer to try to tune it to a "3:00-4:30" brass throw. So, does it seem likely that the current "over gassed" situation is at least partly the cause of the feeding issue?

Note that I don't shoot at a range, so I don't care that it puts the brass forward of the "firing line". I just want to to chamber 100% of time.

Changing your buffer to a heavier one will help with getting your ejection pattern in line with where it is supposed to be (3:00-4:30), and it could help with your feeding issues, if there is harsher recoil it can cause the top round in the magazine to slip up and contact the BCG. The heavier buffer will do nothing for regulating the gas pressure that gets applied to your BCG. Manufacturers nowadays it seems like to size their gas ports to the largest within spec, to make sure they have enough gas to reliably cycle.

Excessive gas pressure from an oversized port will consequently cause your bolt to unlock earlier than it should (not enough dwell time), which is outrunning the pressure drop inside your case that was just fired, which can cause harder extraction (case is still expanded in chamber), and/or blow back of propellant gas. I suggested the buffer due to it being a cheaper part to swap around with to tune up your extraction and dwell time. The way you made your post sound, is that it seems like it's starting to run better with additional lube and more rounds. If that's the case a slightly overgassed AR is not a bad choice for reliability sake. A more extreme overgassed situation (which it doesn't sound like is the case with yours) would cause premature wear to parts, extractor damaging or ripping rims off cases, harsh recoil, etc.

The only way to completely solve an overgassed situation is to replace the fixed gas block with an adjustable one and tune the gas port to correct pressures, often one uses ejection pattern, felt recoil impulse and brass extraction to tune.

I have a feeling if you get your adjustable buffer and play around until you have it ejecting properly (3:00-4:30) and get a couple hundred rounds through and keep it lubed it'll start running fine. But like I and another poster said, it is a new rifle and has a warranty. It just seems like you are right at the break in period for it to start running right, but I may be wrong.

It looks to me by looking at the specs for the Sport II's, that they are using:
1. standard buffer
2. semi-auto (lighter weight) carrier

With those two and if it has a slightly oversized gas port then it make sense where it is ejecting.
 
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Just seeing anybody say that was enough to get me to call. I briefly noted the issue and asked if it is likely to just be due to needing to be broken in. She did not think they needed it but put me on hold and checked. She came back pretty quick and said that yes, about 500 rounds is expected for break in. Not sure if they were just blowing me off or not.

My question to the group...

While researching this I have read that it is common to "over gas" the AR-15 and that seems to be the case for mine since it throws brass to about "1:30". I have ordered the adjustable buffer to try to tune it to a "3:00-4:30" brass throw. So, does it seem likely that the current "over gassed" situation is at least partly the cause of the feeding issue?

Note that I don't shoot at a range, so I don't care that it puts the brass forward of the "firing line". I just want to to chamber 100% of time.

It could be part of it. Feed issues are always kind of hard to diagnose.

In general though, overgassing is not a problem with factory ARs. More gas isn't ideal for a gun, but it usually doesn't prevent it from feeding, it's just sort of needlessly hard on the rifle and hard on you. Can it choke a gun, absolutely, but pretty much every budget 16" AR these days comes overgassed by design to better feed cheap ammo and most of them run OK. Personally, my suspicion is the magazine; maybe your gun doesn't like the Pmags.

My usual approach with anything broken is if I can't diagnose the root cause, I try the cheapest potential solution first. In your case, the first thing I'd check would be a box or two of different brand ammo, the next thing would be a new aluminum magazine, and after that would be the buffer. Sounds like you already have the ammo and buffer, I'd pick up a mag.
 
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Regarding the question of "starting to run better with additional lube and more rounds", that is my hope. The last set of rounds thru each of the two magazines was flawless.
I am mostly waiting to pick up some "proper" 5.56 ammo before the next test. Regardless of .223 vs 5.56 I want to try different ammo to eliminate the possibility that it does not like this stuff for some reason.
 
Just back from my third outing. I am still waiting for the adjustable buffer, but I got some American Eagle 5.56 so I went out for a test.

The quick report is that it worked 100%. Note that I did not load more than 10 rounds in either mag since I want them to have more round count before I try that test again.

I waited until just before shooting to load the mags. I started with shooting off a bench rest this time. The previous two outings I did not take the bench so all shots were offhand. I figured that the rest would help if some of the trouble was the over gas causing more jump and rounds being knocked out of the mag.

So, this was 10 rounds rested from each of the two mags and then 5 rounds offhand from each mag. Thus 30 rounds total without a hiccough.

The throw is looking more like 2:00-2:30 at this point. It will be interesting to see how the adjustable buffer effects that. I suspect I will try it at each weight setting to see how it throws and see if it short strokes at the higher end.

I will report after I have received and test the buffer, but at this point I am thinking it was just a new gun that might have not had *any* issues if I had cleaned and lubed it better and maybe not have loaded the mags all the way to 30 before driving out to the forest.

Thanks again to everybody for supporting an AR newbie (tho a long time shooter).

P.S. If you had not heard, the AR-15 is a very fun gun to shoot.
 
Oops, forgot to note that my testing was with the new 5.56 *and* the original .223. It was not clear from what I wrote that it had not been an ammo issue. In fact it was 10 of the 5.56 and 20 of the .223 used today.
 
Glad to hear it ran well!

Agreed, lots of fun to shoot, cheap, flat trajectory, and with just enough oomph to take out two and four legged game at medium ranges. Whats not to like?

Im a relative AR noob too, bought my first two years ago after 25 years of shooting Garands and Mausers and such. Now Ive got 4, and a Mini14......:)

The kids like 'em too-
Resized_20190323_144157_5390.jpg
 
Given the value oriented aspect of the firearm, and seriously, no offense intended at all... a little more break in was needed.
As you have proven.
Less expensive AR's ( I have many PSA's ) have less finessing done to them. Try an 308 AR... those beasts will really show you about break in, Lol

Remember, the same "break in" can apply to the barrels accuracy. It should show improvement after a few hundred rounds.
If you have the funds, try a variety of ammo in it.
Fire 5 throw away shots to "season" the barrel for the current round selected.. ( believe me it can matter quite a bit ) then fire 5 more of the same factory rounds for accuracy.... same thing for the next factory rounds.. repeat... etc.

Once you have found a factory ammo your barrel likes... buy as much as you can afford.

Deals like this are ammo ( Both the 55gr BlitzKing and 69gr SMK Outback ammo's have been quite accurate in many peoples AR's )
The Buy One Get One aspect makes for a heck of a deal...
I wouldn't consider it blasting cheap ammo... but more precision oriented.

https://globalordnance.com/ammuniti...munition/223-remington/?_bc_fsnf=1&brand=3290

And for those of you with .308's ... 168gr FGMM is currently $16 per 20rds.
https://globalordnance.com/federal-...w-point-20-round-box-gm308m-upc-029465089337/

And the same BOGO deal stands for Aust. Outback 308
https://globalordnance.com/search.p...Outback&section=product&_bc_fsnf=1&brand=3290
 
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