M&P 15 jamming? [Archive] - Glock Talk

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dale mcminnis
12-28-2010, 07:24
Hey guys I'm having a problem with my M&P15.The last couple of time I've shot my M&P15 every few shots either the bolt does'nt pick up a round out of the magazine,or the bolt won't close,and the round,and bolt sticks as the round is going into the chamber.I asked a guy at work who has quite a bit more expirence with AR's said the chamber is dirty sence then I've bought a chamber brush.On a side note I have been shoting some pretty cheap,and probably dirty ammo(I'm on a limited budget,also the magazines are Brownells)So the question is if the chamber is dirty the last time I shot,and it did this I used the chamber brush how do you get enough movement on the chamber brush to clean the chamber?Any,and all help would be very much apprieciated.P.S.I got a new Millet DMS-1 for Christmas seems to be a great scope foe the money.Thanks Dale.

pennlineman
12-28-2010, 07:36
Four things come to mind. Clean the chamber by rotating/twisting the chamber brush in the chamber. Try different magazines and make sure the firing pin retaining pin is not installed backwards. It goes in left to right as the bolt is facing away from you. Make sure you lube the bolt.

Chuche2
12-28-2010, 07:50
Lube it good. They run well wet. The last few years at Camp Perry a lot of the competitors wre using Mobil 1 synthetic motor oil on their rifles.

dale mcminnis
12-28-2010, 07:50
This may be a wus question,but how do you rotate the chamber brush:dunno:?I can't get good enough grip on the cleaning rod.Thanks Dale.

pennlineman
12-28-2010, 07:54
I have an old section of rod with fix T on it. If you have an old section of cleaning rod why not try hooking a set of vice grips to it. Cleaning the chamber should not require a lot of force, go easy.

dale mcminnis
12-28-2010, 07:58
Lube it good. They run well wet. The last few years at Camp Perry a lot of the competitors wre using Mobil 1 synthetic motor oil on their rifles.
I think I am running it pretty wet.I will increase the lube.Thanks Dale.

glock22357
12-28-2010, 08:08
Sounds like it's time for a thorough cleaning. You should disassemble your BCG and clean it, clean the bore, chamber, locking lug area, inside your upper & lower. Then lube with some synthetic motor oil.

Also, grab a PMag or three, and see if that helps.

How many rounds since you last did a complete cleaning? What kind of ammo?

dale mcminnis
12-28-2010, 08:09
I have an old section of rod with fix T on it. If you have an old section of cleaning rod why not try hooking a set of vice grips to it. Cleaning the chamber should not require a lot of force, go easy.Thanks I'll impovize.Dale.

dale mcminnis
12-28-2010, 08:20
Sounds like it's time for a thorough cleaning. You should disassemble your BCG and clean it, clean the bore, chamber, locking lug area, inside your upper & lower. Then lube with some synthetic motor oil.

Also, grab a PMag or three, and see if that helps.

How many rounds since you last did a complete cleaning? What kind of ammo?I clean the gun after every range visit all the way down to taking the bolt apart cleaning,and lubing,but I shot about 600 rounds thru it without cleaning the chamber properly I'm new to AR's and I just did'nt think about it.:dunno:

glock22357
12-28-2010, 08:29
I clean the gun after every range visit all the way down to taking the bolt apart cleaning,and lubing,but I shot about 600 rounds thru it without cleaning the chamber properly I'm new to AR's and I just did'nt think about it.:dunno:

I'd be interested to hear if cleaning the chamber fixes things for you. The only thing I use for the chamber/bore is a bore snake, and I have never noticed the chamber on my rifle being that dirty.

fuzzy03cls
12-28-2010, 08:47
It's not a problem with cleaning. AR's do not need to be cleaned all that much. A dirty chamber is fine for a while & should function just fine. It's either, lack of lube, mags or ammo.
What ammo are you using?

dale mcminnis
12-28-2010, 08:50
It's not a problem with cleaning. AR's do not need to be cleaned all that much. A dirty chamber is fine for a while & should function just fine. It's either, lack of lube, mags or ammo.
What ammo are you using?Rite now silverbear:faint:.

dale mcminnis
12-28-2010, 08:59
Thanks for the great ideas guys still accept any more ya'll have.I'm cleaning it as we speek.Do ya'll lube bolt carier bolt everything?I will be using Triflow with teflon.Thanks Dale.

glock22357
12-28-2010, 09:15
Thanks for the great ideas guys still accept any more ya'll have.I'm cleaning it as we speek.Do ya'll lube bolt carier bolt everything?I will be using Triflow with teflon.Thanks Dale.

You should give some high-quality Synthetic oil a try. A major benefit is that due to the additives in them, cleaning is beyond a breeze. Oils like that are all about stopping carbon deposits, and lubricate like nothing else I've used.

I myself do lube up my BCG inside and out while assembling, lightly.

faawrenchbndr
12-28-2010, 09:30
This may be a wus question,but how do you rotate the chamber brush:dunno:?I can't get good enough grip on the cleaning rod.Thanks Dale.

Dale'

Take a piece of cleaning rod, placed it in a vice.
Leave about 2 inches above the vice.
Heated with a torch, if you have one available, if not use a hammer.
Bend it to a 90 degree angle, this will gave a cheap handle.

dale mcminnis
12-28-2010, 10:22
Dale'

Take a piece of cleaning rod, placed it in a vice.
Leave about 2 inches above the vice.
Heated with a torch, if you have one available, if not use a hammer.
Bend it to a 90 degree angle, this will gave a cheap handle.
Thankyou sounds like a great idea.

MrMurphy
12-28-2010, 11:39
Lube. Lots. Carbines, like women, run better wet.

Better ammo, good magazines. Brownells has the USGI contact at the moment so they're not bad, but try others (MagPul PMags, which are also issued now) because that particular mag may be bad.

cowboy1964
12-28-2010, 14:07
Don't over lube it for crying out loud. Save "dripping wet" for other endeavors :)

NeverMore1701
12-28-2010, 14:16
Don't over lube it for crying out loud. Save "dripping wet" for other endeavors :)

It's damn near impossible to overlube an AR. It is very easy to underlube it.

Gunnut 45/454
12-28-2010, 14:34
I agree with whats been said so far. I would suggest not using teflon as a lube. It tends to buildup over time making things tight! Silver Bear is poly coated ammo. Is a dirty burning ammo. Give it a good scrubiing including the chamber! Lube it up with a good lube like Mobil 1 I use 5w30 oil myself! Try it and see if your problem goes away! If not get a new/different mag! If you still have a problem -try different ammo! Seeing your gun is fairly new it should have M4 feed ramps so that should not be an issue!:supergrin:

faawrenchbndr
12-28-2010, 16:29
Don't over lube it for crying out loud. Save "dripping wet" for other endeavors :)

You can not over lube it,......the first three or four shots will shed the excess.

dale mcminnis
12-30-2010, 11:46
Well I'm fixing to go to the range.I've cleaned everything,and chamber as good as posible.If the store has a good synteyic oil Ill get some.I'll let ya'll know how it went.

8th SPS USAF
12-30-2010, 15:43
We found that if you mix ATF and synthetic oil works great for semi/FA
and semi shotguns Good luck
8th

dale mcminnis
12-30-2010, 17:55
I shot my rifle today same as before shot 20 rnds fine it just started "jaming"more as the range session progressed.I ended up shotting 80rnds probably 20 FTF.The day I posted the first post about this I cleaned it thourly.I did'nt have any mobil 1 on hand so I used the lube I've been using.I used 3 brownells mags,and 1 C products mags.I can't imagine whats going on.:steamed:

Gunnut 45/454
12-30-2010, 18:09
dale mcminnis
O'K ? Did you change the type of ammo? If not try that next! Give another good cleaning- if you have some Remoil use that instead of your Teflon! If not do you have some regular motor oil? Anything but that teflon! Your fallure to feed sounds like your gun is short stroking! Which is usually caused by under powered ammo!! Though the wrong lube will cause it too! :whistling:

faawrenchbndr
12-30-2010, 18:24
What ammo are you using?

nipperwolf
12-30-2010, 18:36
What ammo are you using?

On a side note I have been shoting some pretty cheap,and probably dirty ammo

Rite now silverbear

:supergrin:

As others have said, try some DIFFERENT ammo. While many don't have trouble with that ammo, some do.

dale mcminnis
12-30-2010, 18:39
dale mcminnis
O'K ? Did you change the type of ammo? If not try that next! Give another good cleaning- if you have some Remoil use that instead of your Teflon! If not do you have some regular motor oil? Anything but that teflon! Your fallure to feed sounds like your gun is short stroking! Which is usually caused by under powered ammo!! Though the wrong lube will cause it too! :whistling:No I have'nt yet before long I'm going to order some decent brass ammo,and get some Mobil1.When I first got the gun I put 500 rnds of Wolf military classic no problem,and about 150 to 200 rnds of the Silver bear no problems.I bought 1000 rns of Silver bear thats how I know.Thanks Dale.

dale mcminnis
12-30-2010, 18:41
What ammo are you using?

Silver bear I bought 1000 rnds of it.Thanks Dale.

dale mcminnis
12-30-2010, 18:42
:supergrin:

As others have said, try some DIFFERENT ammo. While many don't have trouble with that ammo, some do.I belive it.Dale.

faawrenchbndr
12-30-2010, 18:45
Try some different ammo.

MisterPX
12-30-2010, 19:49
I put 500 rnds of Wolf military classic no problem,and about 150 to 200 rnds of the Silver bear no problems..

That would lead me to beleive it's not teh ammo. Try this experiment, load one round into a mag, charge weapon, fire, does bolt lock back? If yes, it's not teh ammo. From your previous postings, I'm going to think along the lines of amgazines. Humor me first though, and tighten up your mag catch one rotation. Then try it.


ETA: you did listen to these guys and lube your rifle too? Don't forget teh buffer/spring

fuzzy03cls
12-31-2010, 08:09
Sounds to me the chamber isn't in spec & just doesn't run steel case ammo once the chamber becomes dirty it may push the spec just a hair out & then jam o matic. I had the same issues with wolf in some AR's fine for a mag or 2 then jam after jam.
All I run is SB through 3 AR's for plinking & I never have a problem. If you want to dump your SB ammo PM I'll take it if the price is right.

Remember this is .223 ammo. Not 5.56 ammo. IMHO you should always run 400-500 rds of full power brass 5.56 ammo through the gun before using any steel case.

Gunnut 45/454
12-31-2010, 18:30
dale mcminnis
OK was all that SB the same lot#? Or is it mixed lots? Cause one Lot may be ok then you get one that is out of spec's!! QC is not a Russian trait! Ivan might have had a hangover ! Get some XM193 and see if you still have a problem! PMC is another good brass load thats cheap-under powered but cheap!

dale mcminnis
12-31-2010, 19:07
First of all thanks for all the great ideas,and imput.Happy new year.I have'nt fixed the problems with my gun yet,but am positive with all the help,and sugestions.I'm sure the problems will be fixed.From what I gathered the problem is pointing to the ammo.I think I can sell this silverbear to someone locally if I can't I'll give you a shout fuzzy I think.Anyway I apprieciate all the valuable info.Dale.:cool:

SARDG
12-31-2010, 19:29
This may be a wus question,but how do you rotate the chamber brush:dunno:?I can't get good enough grip on the cleaning rod.Thanks Dale.
Fixed-handle chamber rod:
http://www.midwayusa.com/viewproduct/?productnumber=423606

Brownells carries them, as well.

billwade
01-01-2011, 11:15
a friend of mine had this trouble a little while back. I watched as he shot the bolt was not coming back far enough to cycle. So i check the gas rings in the bolt and they were messed up. We replaced them and the rifle works fine now. Make sure you don't line up the slots.

Fireman1291
01-02-2011, 09:47
Wolf and silverbear are way underpowered. To use that ammo youll need a carbine buffer and a fresh buffer spring. My now sold M&P15T wouldnt run that ammo at all. Try some winchester 5.56 or PMC bronze 223 with your current setup and let us know what happens. Good Luck

dale mcminnis
01-02-2011, 12:56
Wolf and silverbear are way underpowered. To use that ammo youll need a carbine buffer and a fresh buffer spring. My now sold M&P15T wouldnt run that ammo at all. Try some winchester 5.56 or PMC bronze 223 with your current setup and let us know what happens. Good LuckI definatly will.When I first got my AR I bought 500 rnds. of Wolf military clasic it ate it up no problem.Thanks Dale.

Gunnut 45/454
01-02-2011, 20:54
dale mcminnis
Was that the laquer Wolf or the poly Wolf! If it was the laquer Wolf I'd say you have build up in the chamber -very bad and hard to clean out especially at the case neck area of the chamber! That crap affects your cycle rate as it delays the round coming out just enough to short stroke! This why Wolf went to poly coating to many problems with the Laquer!

dale mcminnis
01-03-2011, 06:40
dale mcminnis
Was that the laquer Wolf or the poly Wolf! If it was the laquer Wolf I'd say you have build up in the chamber -very bad and hard to clean out especially at the case neck area of the chamber! That crap affects your cycle rate as it delays the round coming out just enough to short stroke! This why Wolf went to poly coating to many problems with the Laquer!I think the Wolf was poly coated,although it kinda felt almost bear steel the SB is zinc coated.

fuzzy03cls
01-03-2011, 08:23
Wolf and silverbear are way underpowered.
Wolf is. Silverbear isn't.

ArmoryDoc
01-03-2011, 10:04
There are likely two culprits in this diagnosis. Number one is low powered ammo. Better ammo may yield better results.

Number two is the chamber. Many believe that "laquer buildup" is a potential problem. Well, buildup is but not laquer buildup. When you shoot brass cased ammo, the brass expands to seal the chamber, which reduces the amount of gas and carbon blowback through the chamber area. The brass then quickly retracts, pulling itself away from the chrome lined chamber walls and allowing the bolt to pull it free.

When you shoot steel cased ammuntion, the steel isn't as elastic as the brass is. The steel expands to a smaller degree but doesn't "seal" in the chamber like brass does. This allows gasses to flow back through the chamber and those gasses will cause "carbon buildup" on the chamber walls. Shooting the cheaper ammo, which is dirtier (plenty of evidence of that) causes a quick buildup on the close-tolerance walls of the chamber and the more you shoot, the more buildup you have.

Now, in your "cleaning" many neglect, to some degree, the chamber area because it's a little tougher to clean than the bore. If you "clean" but don't really get all the carbon out of the chamber, then run brass cases through it, the brass then expands, as it should, tightly against the chamber walls. Now, because of the several hundred thousanths of carbon buildup on the chamber walls, the tolerance for expansion and contraction has been reduced. The slick chrome lining of your chamber is now coated with rough, sticky carbon, the chamber I.D. is reduced and the round "sticks" to the carbon, which can retard the rearward cycle of the bolt, up to possible terminal failure. Worst case scenario is you'll start pulling rims off the cases and have stuck cases in your chamber. Take an aluminum cleaning rod with you to the range for the times you have to tap out a case.

I know you're still running steel cased ammo but bear in mind this process. I run steel too for practice but my guns are CLEANED. Also, after you CLEAN your gun (CHAMBER) good, like others said, run higher powered "brass cased" ammo for a real test. Good luck.

MrMurphy
01-03-2011, 10:51
Lining up the slots in a gas ring has absolutely no effect on the weapon. They move around with every shot.

Fireman1291
01-03-2011, 17:12
Lining up the slots in a gas ring has absolutely no effect on the weapon. They move around with every shot.

Ummm of course they move but if you offset the 3 from each other, odds are they wont line up during firing. Dont spread bad info please.

NeverMore1701
01-03-2011, 17:30
Ummm of course they move but if you offset the 3 from each other, odds are they wont line up during firing. Dont spread bad info please.

They work fine all lined up. Hell, it works with just one.

MisterPX
01-03-2011, 18:11
Sometimes it works fine without any gas rings at all.

dale mcminnis
01-06-2011, 15:11
Well guys I happy to tell you all problem fixed.I've taken everybodys advice.Moter oils great.I did'nt have any Mobil 1,but I had some regular 5w30 I coated the insides with.I think the bigest improvement was the ammo.I bought 400 rnds of Federal American Eagle.80rnds no stopadges whatsoever.Thanks again.Dale.:thumbsup:

cowboy1964
01-06-2011, 15:17
I ran Tula steel-cased through my M&P from rounds 40-100 without cleaning other than the initial one. No issues. Not a lot of rounds but still, I am satisified so far.

MisterPX
01-06-2011, 15:48
Well guys I happy to tell you all problem fixed.I've taken everybodys advice.Moter oils great.I did'nt have any Mobil 1,but I had some regular 5w30 I coated the insides with.I think the bigest improvement was the ammo.I bought 400 rnds of Federal American Eagle.80rnds no stopadges whatsoever.Thanks again.Dale.:thumbsup:

Good to hear.

Too bad you didn't do it one at a time to determine if it was lube or ammo.

dale mcminnis
01-06-2011, 15:54
I did.Last time I went shooting I followed the same cleaning,and lube advice only thing diferent I used Silverbear,and today I used American Eagle.

dale mcminnis
01-06-2011, 16:04
I did.Last time I went shooting I followed the same cleaning,and lube advice only thing diferent I used Silverbear,and today I used American Eagle.Also the last time I went shooting with the Silverbear I had 15 to 20 failure to feed today with the American Eagle I had none.

demusn79
01-08-2011, 07:49
Ummm of course they move but if you offset the 3 from each other, odds are they wont line up during firing. Dont spread bad info please.

Old wives tale,Don't spread bad info.