Extractor failure

[Pinger5.56]

Hello, I just recently shot my M&P15 Sport 5.56, I put 60rds through it of 5.56 Winchester white box, then around 160rds of PMC 55gr .223 When I got ready to leave I pulled the charging handle to make sure the weapon was clear. I locked back the bolt with my bad lever and when I flipped it forward the rifle went off, the round sounded really weak and when I pulled back the charging handle the round did not extract from the rifle. I had to use a cleaning rod to push out the case from the chamber. I even looked in there and did not see anything. the magazine was not in the rifle I removed the Mag first before sliding the charging handle several times.

I took apart the extractor by removing the pin and noticed that the rubber grommet that goes over the spring was missing. I have a field kit that had another grommet in it and have put that back on there.

My ? is would that rubber grommet being missing keep the extractor from ejecting the round from the chamber after being loaded. Also would this make the rifle go off with just the bolt carrier flying forward after releasing the bad lever. I have tried it again and it has not went off or gotten stuck since. I am still new to these AR15 platforms. I have had several FTF, FTE with the rifle mainly on 5.56rds. Could all of these issues have been related to the rubber little grommet being missing. I knew I should have gotten a Mini14 or a AK instead of this. If I keep having issues I am going to get the rifle repaired and then get rid of it.

Thank you to all your replies.

 

[JaPes]

My ? is would that rubber grommet being missing keep the extractor from ejecting the round from the chamber after being loaded.

The rubber grommet provides extra tension on the extractor. Could be a combination of not enough tension on the extractor and a shallow case rim groove.

Personally, the only time I've had an issue extracting a round (with or without the "o" ring" is when there was some sort of material or construction defect in the cartridge case. I've had the extractor slip over the rim of a case upon extraction. I've had the extractor rip the case rim off.

Also would this make the rifle go off with just the bolt carrier flying forward after releasing the bad lever. I have tried it again and it has not went off or gotten stuck since.

The firing pin floats in the BCG. There is no firing pin block. What you experienced was a slam fire. The primer on that particular round was extra sensitive, the forward momentum of the BCG imparted enough momentum to the firing pin to set off the round.

Chalk that one up to a chance encounter with a sensitive primer. It happens. It's rare, but it happens.

I knew I should have gotten a Mini14 or a AK instead of this. If I keep having issues I am going to get the rifle repaired and then get rid of it.

Pinger, I don't recall your former issues with the rifle. If you are having problems and are just fed up, then you have to do what you have to do.

One word of caution/advice. AK-47's and their variants are a whole world on their own. I've dipped my toe into the AK-47 waters. Which former communist block country does this one come from. Is the magwell cut open properly, is the trunion on straight, is the sight straight, is the barrel pressed in place straight, ... etc ...etc ... etc. If you thought AR-15's were troublesome, AK-47's have the potential to be worse IMO.

If you do get an AK-47, from my minimal research, might as well go all in and get a Krebs Custom. His shop is up the road from me, and his AK's are outstanding (to my newbie eyes).

 

[JaPes]

The issues your 15-Sport are having extracting 5.56 rounds could be due to a combination of:

1. The 15-Sport being intentionally overgassed to be compatible with a wider variety of commonly found, off the shelf, commercial .223 Remington ammo.

2. The 5.56 NATO round's increased pressure over the .223 Remington.

3. Semi-auto BCG + carbine weight buffer.

The increased gas pressure could be causing your rifle to cycle too fast. If you were going to try a remedy to slow down your action when firing 5.56, try installing an inexpensive "H2" buffer.

May not fix things, but it's where I would start.

 

[W.E.G.]

One slam-fire is no reason to condemn a rifle.

Moreover, I don't get it that you were getting ready to leave, so you locked the bolt back on a loaded magazine, and then deliberately tripped the bolt-release lever to let the bolt fly on what?... a live round?

The whole story sounds peculiar to me.

If the case was stuck in the chamber, it could very well have to do with the fact that you shot a bunch of steel-case ammo in it already, and gunked-up the chamber. Even worse than actually shooting steel-case ammo in an AR is the mistake of shooting brass-case ammo in it before you have meticulously cleaned the steel-case residue from the chamber.

If you have your heart set on shooting steel-case ammo, then by all means, get an AK.

 

[JaPes]

^Dude chill. Nowhere in his post did he state he was shooting Russian polymer coated steel case ammo. Nor would polymer coated steel case ammo "gunk" a chamber that bad. The old Lacquer coated, yes. I have to go out if my way to find old style lacquer coated steel case today.

*EDIT*

My apologies to W.E.G. His memory is longer than mine. I found the thread where Pinger shot up some TulAmmo. I am also wrong in my assumption italicized above. Without knowing how Pinger shot the TulAmmo. Slow fire, not a problem. A few mag dumps and the chamber could have become hot enough for some of the polymer on the cases to stick to the chamber.

After reviewing Pinger's posts, it is possible that he didn't clean the chamber of any polymer fouling. I don't know.

 

[JaPes]

Though he did make the mistake of not visually checking the chamber before sending the bolt home. Just pulling the charging handle back and not seeing a case eject does not indicate there's not one in the chamber, as the OP learned the hard way.

Always visually check the chamber. I'll stick my finger in there to feel for an empty chamber.

 

[Chew]

Hello, I just recently shot my M&P15 Sport 5.56, I put 60rds through it of 5.56 Winchester white box, then around 160rds of PMC 55gr .223 When I got ready to leave I pulled the charging handle to make sure the weapon was clear. I locked back the bolt with my bad lever and when I flipped it forward the rifle went off, the round sounded really weak and when I pulled back the charging handle the round did not extract from the rifle. I had to use a cleaning rod to push out the case from the chamber. I even looked in there and did not see anything. the magazine was not in the rifle I removed the Mag first before sliding the charging handle several times.



I took apart the extractor by removing the pin and noticed that the rubber grommet that goes over the spring was missing. I have a field kit that had another grommet in it and have put that back on there.



My ? is would that rubber grommet being missing keep the extractor from ejecting the round from the chamber after being loaded. Also would this make the rifle go off with just the bolt carrier flying forward after releasing the bad lever. I have tried it again and it has not went off or gotten stuck since. I am still new to these AR15 platforms. I have had several FTF, FTE with the rifle mainly on 5.56rds. Could all of these issues have been related to the rubber little grommet being missing. I knew I should have gotten a Mini14 or a AK instead of this. If I keep having issues I am going to get the rifle repaired and then get rid of it.



Thank you to all your replies.

Let me know if you want to sell it.



Sent from my iPad using Tapatalk

 

[Pinger5.56]

One slam-fire is no reason to condemn a rifle.

Moreover, I don't get it that you were getting ready to leave, so you locked the bolt back on a loaded magazine, and then deliberately tripped the bolt-release lever to let the bolt fly on what?... a live round?

The whole story sounds peculiar to me.

If the case was stuck in the chamber, it could very well have to do with the fact that you shot a bunch of steel-case ammo in it already, and gunked-up the chamber. Even worse than actually shooting steel-case ammo in an AR is the mistake of shooting brass-case ammo in it before you have meticulously cleaned the steel-case residue from the chamber.

If you have your heart set on shooting steel-case ammo, then by all means, get an AK.

No I have never shot steel case ammo. I was at the range, I shot 10rds out of 30, dropped the mag and pulled the charging handle several times to make sure the weapon was clear. I put on a BMC gunfighter L3 charging handle and can now use it one handed while keeping the rifle on target. I glanced into the chamber and saw nothing. I locked it back and after shutting off my sight mark reflex sight, I then Flicked the BAD lever with my finger and when it slammed forward it went off.

Upon inspection of the rifle I noticed that the grommet was missing and then replaced it out of my field kit. I do like the weapon but I am used to a rifle not a tonka toy. I used to shoot mini14's and M1's. My last rifle was a mini14 and I miss it but having trouble finding one in my area.

 

[Pinger5.56]

round in chamber

Well I have replaced the rubber grommet and will be taking it out here soon. I really don't want to start all over with another rifle, and I really do enjoy this firearm.

Also to clear things up from my first post, I shot 10rds out of a 30rd mag. I then removed the Mag and pulled back on the charging handle several times to make sure the rifle was clear. I then locked it back with my back lever and then noticed my reflex sight was still on and held the rifle one handed turned it off then flicked my finger releasing the bad lever, this is when the rifle fired, when it slammed forward.

I then noticed that there was a round in the chamber and tried the charging handle, the round did not extract. I had to use a cleaning rod that I had on me to push out the spent case. I inspected the casing and it looked, ok but to me look swollen at the base ring.

Upon inspection I noticed that the rubber grommet was missing from the extractor. I had another one in a field kit I got and replaced it.

 

[JaPes]

I then removed the Mag and pulled back on the charging handle several times to make sure the rifle was clear.

Yanking on a charging handle does not ensure the rifle is clear. What you experienced is the reason why you have to take the time to look into the ejection port, to visually check whether or not the chamber is clear.

The steps I take:

1. Pull mag.

2. Pull charging handle to the rear, lock the BCG back.

3. While keeping the muzzle pointed safely downrange toward the backstop, roll the rifle so that I can view into the ejection port and to the chamber.

4. Once I visually verify there is no round in the chamber, I take the extra step of sticking my finger through the ejection port into the chamber to feel whether or not the chamber is clear.

I then locked it back with my back lever and then noticed my reflex sight was still on and held the rifle one handed turned it off then flicked my finger releasing the bad lever, this is when the rifle fired, when it slammed forward.

You had a round in the chamber because you didn't perform a visual inspection of the chamber. You assumed the rifle was safe. Case stuck in chamber, BCG slams home, the free floating firing pin had enough momentum to set off a sensitive primer. You experienced two things.

1. A slam fire.

2. A negligent discharge. Negligent because you didn't take the correct actions to make absolutely sure your chamber was clear.

I then noticed that there was a round in the chamber and tried the charging handle, the round did not extract.

You didn't have a round in the chamber. You had a spent case. If the case was bulged, then the round might have lit off slightly out of battery. Could have been from when the bolt slammed into it, the round bounced a little, the firing pin slam fired...

You got lucky my friend. Very lucky. If one more thing had gone wrong, then the outcome could have been different.

I do like the weapon but I am used to a rifle not a tonka toy. I used to shoot mini14's and M1's. My last rifle was a mini14 and I miss it but having trouble finding one in my area.

What I am about to say will probably cause some butt hurt, but ...

The AR-15 is a rifle. The basic design has been around since the late 1950's and been on the civilian market since the 1960's. It is not a "Tonka Toy". It doesn't matter a whit to me that you used to shoot Mini 14's and M1's. Because you claim to have this extensive experience with "real" rifles, it utterly baffles me that a marksman of your purported experience practices such lax safe firearms handling.

Your AR-15 failed to extract. That can be attributed to the gun or the ammo. The rest is on you. Your negligence started by not properly verifying your chamber was clear, starting the chain of events that led to the slam fire.

What happened wasn't good all around. Thank god one more factor didn't go wrong or else this could have ended differently.

 

[Pinger5.56]

Yanking on a charging handle does not ensure the rifle is clear. What you experienced is the reason why you have to take the time to look into the ejection port, to visually check whether or not the chamber is clear.

The steps I take:

1. Pull mag.

2. Pull charging handle to the rear, lock the BCG back.

3. While keeping the muzzle pointed safely downrange toward the backstop, roll the rifle so that I can view into the ejection port and to the chamber.

4. Once I visually verify there is no round in the chamber, I take the extra step of sticking my finger through the ejection port into the chamber to feel whether or not the chamber is clear.



You had a round in the chamber because you didn't perform a visual inspection of the chamber. You assumed the rifle was safe. Case stuck in chamber, BCG slams home, the free floating firing pin had enough momentum to set off a sensitive primer. You experienced two things.

1. A slam fire.

2. A negligent discharge. Negligent because you didn't take the correct actions to make absolutely sure your chamber was clear.



You didn't have a round in the chamber. You had a spent case. If the case was bulged, then the round might have lit off slightly out of battery. Could have been from when the bolt slammed into it, the round bounced a little, the firing pin slam fired...

You got lucky my friend. Very lucky. If one more thing had gone wrong, then the outcome could have been different.



What I am about to say will probably cause some butt hurt, but ...

The AR-15 is a rifle. The basic design has been around since the late 1950's and been on the civilian market since the 1960's. It is not a "Tonka Toy". It doesn't matter a whit to me that you used to shoot Mini 14's and M1's. Because you claim to have this extensive experience with "real" rifles, it utterly baffles me that a marksman of your purported experience practices such lax safe firearms handling.

Your AR-15 failed to extract. That can be attributed to the gun or the ammo. The rest is on you. Your negligence started by not properly verifying your chamber was clear, starting the chain of events that led to the slam fire.

What happened wasn't good all around. Thank god one more factor didn't go wrong or else this could have ended differently.

I did turn the rifle side ways and did a quick visual inspection, but I did not like I have done in the past was like you said insert finger into the chamber. I have large fingers and it is hard to get my finger in there even my pinky I have a bore light that I use but I forgot it that day at the range.

Also the comment tonka toy was stating the fact that I am a lager guy and the AR platform seems small to me like a tonka toy, not saying that the firearm itself is a toy or a piece of junk. It's far from that. I enjoy shooting my AR-15 and out at my range there is no range master and sometimes some people show up when you are shooting and they just back there truck right up besides you down range and instead of cousing a seen I tried to pack it up and get out of there. I know I should have check it and this was a dumb *** attack. If you do not think that it did not cross my mind that it could have ended up different, yes it did sir many times. I am glad that It went off at the range and not else where. I am also thanking GOD that no one got hurt.

One more thought, We are all Human and Human is to error. No one is perfect but with firearms one needs to be I know this. I have had this drilled into me my hole life. Thank you for your replies sir, also your knowledge. This will never happen again Thank you

 

[Pinger5.56]

^Dude chill. Nowhere in his post did he state he was shooting Russian polymer coated steel case ammo. Nor would polymer coated steel case ammo "gunk" a chamber that bad. The old Lacquer coated, yes. I have to go out if my way to find old style lacquer coated steel case today.

*EDIT*

My apologies to W.E.G. His memory is longer than mine. I found the thread where Pinger shot up some TulAmmo. I am also wrong in my assumption italicized above. Without knowing how Pinger shot the TulAmmo. Slow fire, not a problem. A few mag dumps and the chamber could have become hot enough for some of the polymer on the cases to stick to the chamber.

After reviewing Pinger's posts, it is possible that he didn't clean the chamber of any polymer fouling. I don't know.

I never said in any of my post that I shot steel case, I said that I had like 500rds given to me as a gift and was thinking about shooting some through it, but changed my mind and did not shoot it I sold it to a buddy that will shoot the hell out of it. Only gun that I shoot steel case in is my Star BM 9mm handgun thank you. I again have never shot any steel case ammo out of my AR15/M&P15 sport. I shot it in my buddies after I sold it to him.

 

[rtquig]

The important thing here is that after this incident, you now know what to be aware of the next time you shoot. Lesson learned, move forward and enjoy you M&P.

 

[jimbo728]

All criticism aside.
A round was in the chamber. It should have been ejected with your efforts but was not. What caused it is my question.
The only time I have experienced this in any semi or full auto rifle, the cause was a broken extractor or the round was not in battery.
Broken extractor cause: A pierced primer causing gasses to damage anything they are exposed to. Believe me, this happens and breaks firing pins too. My suspicion of this is that you stated a round sounded weak.
If you can, examine your brass to see if the struck primers pierced.
FTE happened to me as a result of this happening and it was an M1, NOT an AR. The firing pin and extractor did break due to this.
I don't think your slamfire was intentional but as I`m sure you have learned you need to always visually check. If your bolt closed on the cartridge and did not fire , your "empty gun" could have killed someone.
We all make mistakes. If anyone thinks you are above that, you are dangerous.
Lastly, I hope that bolt assembly gets a close examination before future use.
Get Safe and Stay Safe
Jim

 

[WR Moore]

One word of caution/advice. AK-47's and their variants are a whole world on their own. ..............Which former communist block country does this one come from?

Let me add something here. During the Cultural Revolution the PRC decided that heat treating was a bourgeoisie plot to impede the progress of the revolution. If you're going to AK land, I'd suggest getting Peter Kokalis's book on the AK to find a good one if you're not going to take JaPes advice.

 

[JaPes]

Let me add something here. During the Cultural Revolution the PRC decided that heat treating was a bourgeoisie plot to impede the progress of the revolution. If you're going to AK land, I'd suggest getting Peter Kokalis's book on the AK to find a good one if you're not going to take JaPes advice.

Thank you for the tip.

It's pieces of background knowledge like this that I don't know that make me very hesitant to step into the AK world.

 

[WR Moore]

After some thought and a quick search, I believe what I'd read was in an SOF article "Kalishniklones, a Consumers Guide to AKs". I do believe the same contents are in one of his books. A back issue would probably be cheaper.

 

[Rastoff]

The AR is to the modern sporting rifle world as the 1911 is to the defensive pistol world. It takes just a tad more maintenance. This is just a simple fact of life. The benefit of this extra care is a much more accurate rifle.

An average AR is a 1MOA gun right out of the box. There isn't an AK made that can make that claim. The new Mini-14 is a 2MOA gun right out of the box and can be made better with some modifications. The older Mini-14 was lucky to get 5MOA out of a new gun.

While the Mini-14 is a good gun, there are some drawbacks. It's not as easy to add an optic or other accessories. The accessories that are available are not as prolific as the AR. The gun is much heavier than an AR. The Mini-14 piston system is extremely reliable though and is very easy to maintain. Taking the bolt out is easy. Putting it back in takes some practice. Kind of like a puzzle, but once learned isn't too hard to do.

I like the Mini, but I like the AR better.

 

[Pinger5.56]

Lesson learned

Thanks to all for the replies and the bitching out also, I needed those. I have just today took it to the range after putting in a extractor kit, I had a local gunsmith check it over for me and all he suggested was to replace the extractor spring and the rubber grommet, he said that the extractor looked fine besides that. That was done today. I now use my bore light after shooting from now on. I also use my lock that came with the rifle to lock out the bolt if I am going to mess with my optics.

I shot like 100rds+ through it today and it performed flawlessly. I think that was a weak primer in that one that got stuck. Not sure how it got stuck. I am here soon going to get like 120rds of 5.56 and run it through it so see if I still have any issues with the 5.56 ammo. I use PMC .223 bras FMJ 55gr every time I go to the range. I have shot some 5.56 Winchester, Independence and some Federal with some issues in the past. I think most of the issues are due to the rifle still in that breaking in period. I shot those rounds in it the first day I got the rifle after cleaning it before going to the range.
I like this rifle a lot and want to keep it, its just that sometimes I feel like it cannot mount the rifle correctly due to being a larger man. Even with the butt stock extended all the way out, also I cannot seem to get a good check weld on that butt stock that came with it. Is there a check riser I could get or maybe a Mapul butt stock that has a check riser that I could get, that is all I need to make this a Black Magpul M&P15 sport edition. All suggestions will be considered. Thank you!!

Again, I just want to thank everyone who replied to this issue and to all the one's out there that gave it to me in a proper bitching, Thank you all!!

 

[JaPes]

Pinger. I'm sorry if I was harsh. I made a total of two mistakes that could have killed me if just one more thing had gone wrong. I want to make sure that you know that I'm not the type to throw stones for I live in a glass house.

I had a Ruger SR1911 fail to return to battery on a live round. The slide was stuck rearward enough to keep the hammer back. My brain took a break, and I stupidly bumped the rear of the slide with my fist. The idiot move was that I kept my finger on the trigger. Bump the slide, slide rides home, finger on trigger ... negligent discharge right into the concrete floor of the range at an angle, then into the backstop. I stopped right then and there, packed it up, and left the range to go change my underwear.

Number two was a lapse in concentration while reloading .357 Magnum.

^ Had to throw out the underwear after this mess up.

 

[rojodiablo]

Pinger, curious to the year of your rifle. My Sport does not have the grommet, and its' fine. On the other hand, my DPMS did not have the grommet either, and the extractor failed at only 5500 rounds or so. (Very early demise.)I replaced it with a known good quality extractor, and then added the grommet, though in most instances, the grommet is not necessary at all.
FWIW, my Sport has well over 12K thru it, and is still on the original extractor, no upgrades.
My hunch is the extractor was not a very clean cut from day 1, or had a soft spring.

As to the slam fire; those are pretty rare, and I would say it was a symptom of the extractor previously pulling the cartridge just up off the seat of the chamber, and a little extra bounce or something of that nature sent he round off on the bolt closing. I will say: VERY RARE. I've been shooting AR's for over 2 decades on and off. I have worked with them, and rebuilt and serviced them, and that just for the most part does not happen. I'm also willing to imagine that you might have had a piece of cartridge rim in the bolt face if the rifle was not extracting; the extractors can rip off a little chunk of metal from a case if the case is stuck; if this was still in there, then it could have become dislodged and at the right position been in there to strike the primer when the bolt closed.
All speculation....... to really know, you need to shoot the rifle a good bit more

If the rifle ever acts funny, take a look at the casings you just went thru. They might tell a story or show you a sign that you need to clean, correct or tune something.

 

[rojodiablo]

Pinger. I'm sorry if I was harsh. I made a total of two mistakes that could have killed me if just one more thing had gone wrong. I want to make sure that you know that I'm not the type to throw stones for I live in a glass house.

I had a Ruger SR1911 fail to return to battery on a live round. The slide was stuck rearward enough to keep the hammer back. My brain took a break, and I stupidly bumped the rear of the slide with my fist. The idiot move was that I kept my finger on the trigger. Bump the slide, slide rides home, finger on trigger ... negligent discharge right into the concrete floor of the range at an angle, then into the backstop. I stopped right then and there, packed it up, and left the range to go change my underwear.

Number two was a lapse in concentration while reloading .357 Magnum.

^ Had to throw out the underwear after this mess up.

After those 2...... the doctor feels you need to drink more BEFORE you shoot.

Ergo- the plausible deniability factor!!!

 

[Maddmax]

The new Mini-14 is a 2MOA gun right out of the box and can be made better with some modifications. The older Mini-14 was lucky to get 5MOA out of a new gun.

Easy there... I have a 37+ year old 181 Mini 14 that's been a tack driver from day one. With the different twist rate (1 in 10) reloading goes a long way too. It was the following years that they started having the problems and the Mini's went down hill. That stupid Ranch Rifle led the way.

And for the record. I have NEVER had ANY problems or issues with my Mini 14. I also own MSR's in more than a few flavors and no body's fan boy.

 

[JaPes]

I believe the Mini-14's decline was due to the manufacturing equipment being worn out and producing parts out of tolerance. I've heard the same things Maddmax says about the older Mini 14's. I don't know how long ago it was (couple years?) that Ruger retooled the Mini-14 manufacturing equipment and then all of a sudden the Mini-14 was back to it's former glory.

 

[Maddmax]

I believe the Mini-14's decline was due to the manufacturing equipment being worn out and producing parts out of tolerance. I've heard the same things Rastoff says about the older Mini 14's. I don't know how long ago it was (couple years?) that Ruger retooled the Mini-14 manufacturing equipment and then all of a sudden the Mini-14 was back to it's former glory.

It was after the 182 and into the 183 series they started getting the bad rep. "We" wanted a 7.62X51 Mini (they even had it advertised in the catalog), I had one on order but they never went into full production and went to the 7.62X39 Ranch Rifle insted (big dud). Colt's started really taking off and for the most part dominated the market back then.

Same time Military surplus ammo was cheap and easy to find. That matched and shot well (enough) out of the Colts,but the Mini's 1 in 10 twist didn't shoot it all that well That also didn't help the Mini's groupings or popularity back then.

I've yet to add a new Mini to the collection. But I did go with the Ruger SR556 piston and do like it.