Odd M1A failure...

Posted: 9/5/2004 2:19:56 PM EDT

I have a recent vintage M1A Load from Springfield. I use only USGI mags purchased from Coles. I use only Mil spec surplus ammo, Port, Hert, and Aus, no Indian! Now that that is out of the way.

Mid way thru my recent range adventure my M1A decided it didn't want to play nice any more. On the third mag the rifle would fire, extract, weakly eject and return to battery. Only one problem, it would not strip a round out of the mag. When you pulled the trigger you would hear a click as the firing pin feel on an empty chamber. Yes I did unload all the mags and reload them to insure the rounds were seated properly.

I tried a half a dozen mags all with the same result. My plan is to send this rifle back to Springfield but I was curious if any of you had seen or heard of this type of failure. The guys at my range (many big time M1A guys) were all puzzled.

Your thoughts?

Regards,
Gary

Posted: 9/5/2004 2:39:10 PM EDT

[#1]

You didn't tell us if this rifle was brandy-new, or broken-in. Makes a difference.

Strip, clean, lube properly, and try again. Maybe new op-rod spring? Wouldn't hurt to have a spare, as it's irreplaceable, and does wear out.

It is most odd that the rifle works OK with the first 2 mags, and malfs on the third. Argues against a receiver mis-configuration.

Another possibility is marginal mag springs, maybe even misconfigured/rough feed lips.

If no joy on the above, send the thing back. If prob is mag springs, don't expect SA to properly diagnose.

Posted: 9/5/2004 2:51:27 PM EDT

[#2]

What RAF said +++

If this is a new rifle for you, I'm betting on the lube issue. Too many people run these things without proper lube. Really lube the areas that the oprod moves in the rail and pivot points etc. That bolt should SNAP forward when you release it.

Posted: 9/5/2004 2:51:28 PM EDT

[#3]

Have you given the gas system(cylinder, piston and barrel port) a good cleaning? Is the gas cut-off functioning properly?

Posted: 9/5/2004 4:28:04 PM EDT

[#4]

Agree with all the above. Also, measure the length of the operating rod spring. It needs to be 15.25 " long + or - 1.00 ". If not, replace it. Use grease not oil for lubrication.

Posted: 9/5/2004 4:36:07 PM EDT

[#5]

short cycle, loose gas nut.

check for a loose gas nut it may have come loose during fring. NM spec is 15 ±2 foot pounds. If the plug is loose tighhten then mark the plug in realtion to the lock so at a glance u can tell if it has loosened.

Posted: 9/5/2004 5:21:34 PM EDT

[#6]

Your op-rod guide could be loose also. It will get the op-rod in a bind and not let it cycle all the way to the rear and strip a new round.

Are you sure the gas plug isn't partially turned to the grenade position?

Posted: 9/5/2004 6:21:55 PM EDT

[#7]

Thanks for all the feedback... Let's see if I can answer the comments.

The rifle has been fired approx. 300 times. I clean the bore with break-free CLP and use Tetra grease on all the parts mentioned above. The bolt snaps back firmly. I found it odd that the empty shells barely were ejected from the rifle. I suspect some sort of gas malfunction. Intresting enough however, the bolt would go into battery but somehow it just "by-passed" striping a round out of the magazine. Odd indeed. Well, I intend to contact Springfield Tuesday and I'll let you all know what they have to say.

Thanks again for all your comments.

Regards,
Gary

Posted: 9/5/2004 8:44:03 PM EDT

[#8]

(As posted above)------Did you you check your gas plug for correct tightness?

Posted: 9/5/2004 10:23:45 PM EDT

[#9]

If it feeds when you cycle it manually, I'd follow the advice above and check the gas cylinder nut. They have been known to loosen up.

Posted: 9/6/2004 3:13:49 AM EDT

[#10]

Quoted:
1The bolt snaps back firmly. 2I found it odd that the empty shells barely were ejected from the rifle. I suspect some sort of gas malfunction. 3Intresting enough however, the bolt would go into battery but somehow it just "by-passed" striping a round out of the magazine.

[1] Not a spring problem if by "snaps back firmly" you mean closed action. Fire one round and see if
it locks open on an empty mag.
[2] Slow ejection with proper lube sounds like not enough gas.
[3] The spring is closing the action but the bolt isn't getting all the way back to where it can
strip a new round from the mag. Again sounds like not enough gas to push the op-rod fully open.

I agree with the other guys, it's a loose gas plug or the gas valve is partly closed.
On match conditioned rifles one of the things they do after they fix the front band to the gas cyl.
is to epoxy the gas valve in the proper position.

Posted: 9/6/2004 4:11:45 AM EDT

[#11]

Consensus is weak recoil which is caused by not enough gas pressure.

Assuming 7.62mm NATO ammo and USGI magazines: Most common causes of this are the spindle turned toward the "grenade" setting, or a loose gas cylinder plug.

-- Chuck

Posted: 9/6/2004 4:22:30 AM EDT

[#12]

Quoted:
Consensus is weak recoil which is caused by not enough gas pressure.

Assuming 7.62mm NATO ammo and USGI magazines: Most common causes of this are the spindle turned toward the "grenade" setting, or a loose gas cylinder plug.

-- Chuck

Definately sounds like a short stroke problem. Though it could be every mag you got has a weak spring... (doubtful)

Check that gas valve out... its usually the culprit.

Do you have a Gas system cleaning tool? They usually look like a octagonal plastic handle with a drill bit coming out of each end.

its not probable with only 300 rnds down the gun (TOTAL?) but if you shoot that thing and never or rarely clean the gas system out, you can get short strokes.

To use the tool you must take the nut on the front of the gass system out, remove the piston and scrape the carbon out of the inside of it.... then put the tool away and wipe off all the carbon off the outside of piston and the sleave it rides in... if they get gummed up really good you can short stroke.

Posted: 9/6/2004 6:53:51 AM EDT

[#13]

Agree with Top Prop, short stroking, check the gas port and the rest of the gas system, it does not take much to cause this.

Posted: 9/6/2004 8:12:24 AM EDT

[#14]

Thanks for all the feedback. I went back to the rifle and checked the gas plug. I found that it had some "play" in it.

Specifically, I had to tighten it about 1/2-2/3's of a revelution til it was snug. Would this be enough to cause the malfunction I observed or should I still send the weapon back to Springfield for evaluation?

Regards,
Gary

Posted: 9/6/2004 8:19:46 AM EDT

[#15]

yes the loose gas plug will cause the short stroking...

Posted: 9/6/2004 10:21:40 AM EDT

[#16]

Quoted:
Thanks for all the feedback. I went back to the rifle and checked the gas plug. I found that it had some "play" in it. Specifically, I had to tighten it about 1/2-2/3's of a revelution til it was snug. Would this be enough to cause the malfunction

Regards,
Gary

Absolutely! Check that thing with your fingers before every shoot....

On my old NM rifle I did what one of the fellas up above said... Torque it to specks then put a mark on it so that if it's out of alignment you can tell at a glance... either sribe a line in it, or just use a dab of fingernail polish (etc).

I still send the weapon back to Springfield for evaluation?

I wouldn't unless it continued short stroking and you couldn't figure it out with the advice you've seen on this thread....

Posted: 9/6/2004 10:36:02 AM EDT

[#17]

The guys at my range (many big time M1A guys) were all puzzled.

obviously not

Posted: 9/6/2004 10:45:59 AM EDT

[#18]

Quoted:
The guys at my range (many big time M1A guys) were all puzzled.

obviously not

Ouch! I'll be sure to tell them.

Just goes to show that everyone can learn something new when they listen to the wisdom of others. I appreciate these forums more and more.

Happy Holiday,

Gary

Posted: 9/6/2004 11:45:23 AM EDT

[#19]

Quoted:
Thanks for all the feedback. I went back to the rifle and checked the gas plug. I found that it had some "play" in it. Specifically, I had to tighten it about 1/2-2/3's of a revelution til it was snug. Would this be enough to cause the malfunction I observed or should I still send the weapon back to Springfield for evaluation?

Regards,
Gary

That's why you have the combo tool stashed in the stock (and in your range kit) to check/fix this. Your problem as described is 99% caused by the plug loosening.

Posted: 9/6/2004 12:41:28 PM EDT

[#20]

I am a bad M1A Owner as I do not own the tool you mention.

I will however be aquiring one ASAP.

Regards,
Gary

Posted: 9/6/2004 1:59:07 PM EDT

[#21]

Quoted:
I am a bad M1A Owner as I do not own the tool you mention. I will however be aquiring one ASAP.

Regards,
Gary

OH MAN!!! LOL

You can usually find them a gunshows used for $2.00-$5.00 . FRED's has new ones IIRC. You might also think about getting the wrench that holds the cylinder. (Brownells or Fulton Armory)

Then you'll have to pick up a couple of...

It never ends!

Posted: 9/7/2004 3:18:54 AM EDT

[#22]

Standard 1/4" drive socket set will have the right socket for the gas cylinder plug. The M14 combo tool does fine too, but no need to wait until you have it.

-- Chuck

Posted: 9/7/2004 8:16:19 AM EDT

[#23]

Just like I thought loose gas plug.

Side note when you re tighten, put some antiseize on the threads I use nickle base, but tetra grease will do. Thiose threads are fine and Stainless. the gas wrench is nice to have in a field bag, But I find a padded vice works from home. 100 inch pounds is plenty tight. the gas plug is something you dont want gorrela tight.

Posted: 9/7/2004 1:50:54 PM EDT

[#24]

Quoted:
100 inch pounds is plenty tight. the gas plug is something you dont want gorrela tight.

+1

Don't know about putting any antisieze or such on them though...

I'd spend the money for the gas wrench along with the combo tool....

A broken shell extractor (you can use a chabmer brush too with a one section of cleaning rod as well.. I used to keep this in my stool for matches) is another good thing to have, you won't realize its value until you need it... usually in the middle of your 300 rapid fire!

when you are well on your way to cleaning it...

or atleast that how i remember it

Posted: 9/7/2004 5:02:55 PM EDT

[#25]

NoName,

Right you are. It never does end! Next is a scope mount and a nice optic for my rifle. Ugh...more $$$$$

Oh well, I hope the kids like weapons cause that's they're getting from me when I croak!

Thanks again to all those who posted to this thread.

Regards,
Gary

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