M1A: FTE diagnosis and "how to clear" drill?


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Buckskinner
March 6, 2009, 11:27 PM
Took the M1A to the range for the first time.
Went through about 100 rounds testing mags and POI.
Several times I had a "stove pipe" type failure to eject.
So, live round in the chamber, with the bolt closed on the empty brass, mouth up. How does that happen?

What is the immediate action drill for this malfunction?

Details:
There's a Sadlak scope mount in place.
I was shooting FNM-60 or something like that. Old but in great and shiny shape.
There was a bit of gunk around the gas cylinder lock and cylinder. Is that normal?

My instinct says clean the ejector, and delube the gas cylinder/piston...



What say ye?

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briansmithwins
March 6, 2009, 11:52 PM
If you have room with the scope mounted I'd sweep my strong hand over the empty brass and knock it loose. Then I'd palm strike the charging handle to confirm the bolt if all the way forward.

M14s are typically run with no lube in the gas piston. If you have corrosion problems try very light oil.

Does the ejector move freely when you compress it with a tool?

BSW

Buckskinner
March 7, 2009, 12:00 AM
The ejector moves after some initial difficulty. It seems stiff and gunky to me.
I'll strip it and clean it all out. Oil the spring and inside the channel?

longdayjake
March 7, 2009, 12:03 AM
what grain bullets are they and what length barrel you shooting?

The socoms wont cycle 175 grainers at all and they struggle with 168 grainers too but can usually do okay.

Buckskinner
March 7, 2009, 09:19 PM
Well, the ammo was W.German surplus w/NATO cross. 147 gr?
Barrel is standard 22".
What does the bolt face supposed to look like? The ejector angle is at a different angle to the middle of the bolt face.
Can the ejector be put in the wrong way?

lipadj46
March 7, 2009, 09:52 PM
So as I understand this is what happening?

The gun goes bang the round is extracted as the bolt goes back, the spent case gets spun out, the next round is fed up and as the bolt goes forward to feed the next round the spent shell gets caught in the bolt?

Is this correct? When you say mouth up you mean the rim end is caught in the bolt or open end gets caught in the bolt? Or is it geting caught between the bolt and the scope mount?

How far is the brass being ejected normally?

Is this new or used? If used have you cleaned out your gas vent? Is your gas valve open all the way? Is the gas cylinder plug tight (sometimes they loosen up while shooting)? Make sure it is cleaned and lubed, M14s need grease.

The ejector is usually pretty stiff but you can take the bolt apart and see if it is gunked up. Just a helpful hint get yourself a spent 30.06 shell or a bolt dissasembly tool from LRBarms.com (they sell a good steel version). The 30.06 shell allows the bolt stay open so you can remove/install the exctractor without the ejector flying across the room.

Can the ejector be put in the wrong way?

No but bolts can be fun to get back together.

TexasRifleman
March 7, 2009, 09:58 PM
No but bolts can be fun to get back together.

No kidding.

If you want to try to take the bolt apart go ahead and buy the tool for that, it makes it immensely easier.

Ask me how I know...... :banghead:

Polar Express
March 7, 2009, 11:48 PM
I haven't shot mine yet, but I'm looking forward to learning about it. Thanks for starting this thread.

TexasRifleman & Lipadj46: What tool are you referring to, and where can I find it? Is that the one from LRBarms.com? If you were to make a list of all the books and tools that would be a good 'starter kit' for a new M1A owner, what would you put on that list? Mine is a standard, so it came with NOTHING.

Thanks!

lipadj46
March 8, 2009, 12:00 AM
http://lrbarms.com/accessories.html

Scroll down to the bottom of the page.

- A combo tool is nice for the wrench and little pry bar to open the trigger guard plus it fits in the butt stock.
- A set of punches with a 3/32" punch
- 2 drill bits (forget the exact size) and some sort of handle to clean out your gas vents. Sadlak makes 2 nice but overpriced tools to do this.
- A spent 30.06 case to change out bolt guts.
- The army field manual that comes with the M1A is about all you need (along with internet forums and youtube)

That's about it. Maybe also a brass hammer or big brass punch. The M14 is a nice simple design and the fact that you only need a wrench to disassemble it 85% of the way speaks volumes of the designer.

Polar Express
March 8, 2009, 12:05 AM
Thanks! I scrolled to the bottom, and saw the bolt tool. is the little multi-wrench thinggy in that cleaning kit?

pgeleven
March 8, 2009, 12:19 AM
If you want to try to take the bolt apart go ahead and buy the tool for that, it makes it immensely easier.

i would recommend watching someone else do it first, unlike my dumba$$ who went solo and watched parts go flying, then spent a good hour busting my knuckle trying to get it back together. i even made up a few new swear words while doing this and im mad i didnt write them down

Buckskinner
March 8, 2009, 12:23 AM
l'46:
The rifle is new to me. Its a 69xxx SAI, with all USGI parts.
Its spent some time at SEI before I got it, and it should be running like a top.
I cleaned the gas system, the piston was shiny clean. I gave it a wipe with CLP.
I didn't torque the gas cylinder plug, but I did find marks from the previous owner. I didn't check the alignment of the gas tube to barrel.
It really shot fine except for these malfs, but having traded an HK for it, which never ever malfed, I'm concerned that this is a bit high strung. I don't want to believe that...
While the scope mount is installed, there is no scope mounted.
Normally the brass goes forward and slightly to the right of my "shooting lane" about 6'.
The ones that get stuck are held by the rim between the bolt and front of ejection port.
And yep, somehow its loading one from the mag into the chamber before the brass gets caught and holds the bolt open.

Are you saying that with the bolt closed on the '06 case, you can drive the pin up from the bottom of the bolt, then retract the bolt from the closed position, and be able to manage the disassembly just like that?
Thanks.

lipadj46
March 8, 2009, 12:24 AM
Yes, you can just use a wrench and a screwdriver to pry the trigger guard but the combo tool is a nice to have. If you can find an Otis 7.62 sniper rifle cleaning kit for $50 or under it is nice compact cleaning kit, you will not need another.

lipadj46
March 8, 2009, 12:30 AM
Are you saying that with the bolt closed on the '06 case, you can drive the pin up from the bottom of the bolt, then retract the bolt from the closed position, and be able to manage the disassembly just like that?
Thanks.

Pretty much the 30.06 shell is long enough to hold the bolt back enough that you can use a screw driver to pry out the extractor (you use a screw driver to pry not to drive it out from the bottom). The shell obviously holds in the ejector that is under tension and would normally go PING and fly across the room and it will also hold the ejector in while you put the extractor back in. It can be done with a vise and some patience but that ejector can shoot like 20 ft and gets very frustrating.

Just keep shooting it and see if it loosens up. It can't hurt to swap out the ejector and spring. They are cheap and I believe numrich has them in stock. Also if you have not grease the bolt roller with a spent .45 case and put a very thin layer of grease on all the metal to metal "sliding" points like the little channel where the op rod runs and where the bolt runs. Also put a thin layer of grease on the op rod spring. Sounds like a nice rifle and if it was at SEI then it should be good.

WardenWolf
March 8, 2009, 12:47 AM
Most stovepipes occur due to your gun not liking that particular type of ammo. Often with softer loads that don't vigorously drive the action to the rear. I'd venture to say your older ammo wasn't going "boom" as well as it should, and the gun was short stroking on it.

Buckskinner
March 8, 2009, 01:08 AM
I see what you mean now.
I dug up a combo tool that came with the rifle. Duh.
No apparent issues with any parts.

If the bolt, gas, and magazine systems are functioning properly then this is probably caused by at least one, if not both of the following factors:


Older ammo?
Scope mount interfering
with ejection,

By the way, it shot like a frickin' dream besides this. I absolutely love this rifle...Not sure if it will replace my M1...now that I've shot them both, I will have to go back to the M1 and compare a bit. That box mag thing takes a lot away from the sweet lines of the M1.

lipadj46
March 8, 2009, 11:59 AM
Most of the newer mounts of that type have been tweeked not to affect ejection. I have the Smith weaver mount and have not had problems. I have heard a few issues with the german ammo but they have been around thin brass and corrosion in battle packs due to acidic paper. I would buy some Prvi Partizan match ammo and see if the problem continues to happen.

Buckskinner
March 8, 2009, 01:36 PM
'Wolf, I think you're right on the money too.

To cock the hammer, the bolt must go all the way aft in the receiver?
So, when I cleared the stovepiped brass and drove the op rod forward, the trigger wasn't set.
When applying immediate action to the op rod, the extractor hadn't grabbed the rim, so it would've became a double feed, had I let fly.

So, I dropped the mag, pulled the op rod back and shook out one round. Then without letting the op rod "fly", close it, and whack it to get the extractor over the rim.

I'll have to check it across the other surplus.
By the way this was either "LOS MS 37-63" or "FNM 80-64".

Thanks for info guys. I didn't know this was a possibility with older ammo, and I'll keep a much closer eye on it.

Looks like I'll keep the "Go" mags filled with the Aussie...

lipadj46
March 8, 2009, 02:00 PM
It could be a number of different things but with M14s it usually comes down to bad ammo, bad mags or a dirty bore (usually from ammo with a tar sealant).

WardenWolf
March 8, 2009, 04:03 PM
Well, the bolt doesn't necessarily need to go all the way aft to cock it; different actions cock at different points in the stroke. However, for proper ejection it needs to vigorously drive it to the rear. Ever pulled a bolt slowly on a rifle? Chances are the spent case just barely rolls out of the action, or doesn't eject very far. Pull it fast, though, and it ejects properly. This is because the ejector needs to hit the case fast and hard to properly eject it. Slowly pulling the bolt results in the extractor not hitting the case hard enough or in the right place to eject it. The stovepiping combined with the failure to recock confirms it, though. It's definitely short stroking. Change your ammo, and you'll be fine.

madcratebuilder
March 8, 2009, 08:12 PM
I cleaned the gas system, the piston was shiny clean. I gave it a wipe with CLP.

Gas cylinder and piston should be clean and DRY.

Sounds like an ammo problem to me.

I have the a Sadlak mount and no problems.

If it's an all usgi parts rifle it should not be the bolt or extractor.

Clean it good and try a different ammo.

Evil Monkey
March 8, 2009, 11:57 PM
This is because the ejector needs to hit the case fast and hard to properly eject it. Slowly pulling the bolt results in the extractor not hitting the case hard enough or in the right place to eject it.

I'm pretty sure the M1A uses a spring loaded ejector like the AR15.

lipadj46
March 9, 2009, 12:01 AM
It is but it is not like it actively pops out correct? My understanding is that it relies on the bolt stopping abruptly and the momentum of the empty shell compressing the spring and then getting ejected. so if the bolt does not slam back with enough force (the bolt is designed to ht the back of the M14 receiver) then the shell will not have enough momentum to compress the ejector spring to eject with enough speed. If that makes any sense.

briansmithwins
March 9, 2009, 12:07 AM
It is but it is not like it actively pops out correct? My understanding is that it relies on the bolt stopping abruptly and the momentum of the empty shell compressing the spring and then getting ejected. so if the bolt does not slam back with enough force (the bolt is designed to ht the back of the M14 receiver) then the shell will not have enough momentum to compress the ejector spring to eject with enough speed. If that makes any sense.

Try this: with the bolt open place a empty shell on the bolt head, compressing the ejector and under the extractor. When you let go the empty brass should be launched out of the rifle. BSW

lipadj46
March 9, 2009, 12:23 AM
Sorry just trying to get the process down in my head...

So does the extractor hold the ejector plunger down (that is does it hold the shell pressed against the bolt face so the ejector spring is tensioned) while the bolt is extracting the shell? Then once the shell is free of the bore, the ejector can push the shell forward and the extractor can move off to the side a bit allowing the shell to eject?

I will take a close look in the evening tomorrow.

WardenWolf
March 9, 2009, 07:05 AM
I'm pretty sure the M1A uses a spring loaded ejector like the AR15.

If the bolt is not moving fast enough as it moves past the ejector, the case will not be in the proper position for ejection when it impacts it, and the ejector will not release as crisply as it should, resulting in lower striking force. Both combine to produce unpredictable ejection characteristics. It's the ammo. Guaranteed.

Evil Monkey
March 9, 2009, 08:44 AM
If the bolt is not moving fast enough as it moves past the ejector, the case will not be in the proper position for ejection when it impacts it, and the ejector will not release as crisply as it should, resulting in lower striking force. Both combine to produce unpredictable ejection characteristics. It's the ammo. Guaranteed.

Your way of explaining what's happening is describing that the M1A has a fixed ejector. It does NOT have a fixed ejector, it has a spring loaded plunger type ejector just like the ar15.

As far as I understand, spring loaded ejectors practically have the same ejection force regardless of how fast the bolt is reciprocating.

30Cal
March 9, 2009, 03:57 PM
I am doubtfull that the problem will clear with cleaning and/or lube.

Stovepiping failures on an M1A almost never happen except when a scope mount is in place. It's a pretty simple matter to confirm that.

You can mess with the ejector plunger spring length (pretty cheap to replace) and maybe the shape of the ejector plunger face and see if it clears.

Gewehr98
March 9, 2009, 04:11 PM
Are there any brass marks on it?

If so, you're that much closer to discovering the source of the stovepipe problem. ;)

Buckskinner
March 9, 2009, 09:46 PM
Might be helpful to some:
Section III, Chapter 18 Functioning, a) Semiautomatic, (2) (d) Ejecting is removing the empty cartridge from the reciever. As soon as the bolt has withdrawn the empty cartridge case clear of the chamber, the force of the ejector spring and plunger pushes the bottom edge of the cartridge base away from the bolt face, throwing it out and away from the receiver."

On the underside of the scope mount there are very few brass marks, though the ones there are in a pattern.

I just have more to pay attention to during the next range visit.

Thanks for the insights.

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