View Full Version : Help troubleshoot M1A/M14
I have a standard Springfield M1A. I have had it for several years but have put only a few hundred rounds through it. Recently it has not been feeding the next round. Seems to fire fine and cycle the bolt. With the next pull of the trigger I get a click of the pin dropping but there is no round in the chamber. It happens every time. At first I was getting a what Kyle Lamb would call a bolt over base malfunction with the round half loaded but now it doesn't pick up the round at all.
If I cycle the bolt then it loads the round fine. I have scrubbed everything and lubed thoroughly. I have tried several magazines (GI) including a new high quality mag. Around the time this started a friend had his gunsmith friend install a Springfield scope mount and scope but I don't see how that could possibly be related. Anyone have an idea what is going on?
Thanks.
Check to see if the screw/bolt from the mount is protruding too far into the receiver...
Spooky
Eric Kozowski
02-01-09, 23:44
My initial thought, and I'm no M14 expert, is that the rifle is short stroking. Check your gas system and make sure everything there is good. Additionally, try different ammo and see if that makes a difference. It might be "weak" ammo. Make sure nothing is dragging or binding up in the operating system.
Hopefully, an M!4 expert will chime in.
Check to see if the screw/bolt from the mount is protruding too far into the receiver...
Spooky
Definately do this first. If nothing is obvious, take it back. If the 'Smith is reputable, he should find the prob and fix it (no charge), if it was non-existent before him. Give him a chance. If he FAILS, then fail him back, every chance you get and find a good guy!
60
I believe that it is short-stroking and you need to check the spindle valve on the right side of the weapon and ensure that it is in the 12 o' clock position and not the horizontal position that is used for firing rifle grenades. Second thing would be to use ammunition that is known to work.
Where is the brass ejecting? A M1A/M14 that is cycling correctly will eject the brass at about the 1-2 o'clock position. If they a re dumping out at 3 o'clock, the bolt is slowing down. Possible causes could be 1) ammunition, 2) gas system, 3) friction, 4) binding, 5) bad magazine
1) The ammunition used in a M1A/M14 needs to use a medium burn rate powder to perform best. Too fast and you could end up with low port pressure. Too slow and you could end up with too much port pressure. The standard for comparion is 4895 powder. NATO spec ball ammo typically uses ball powder that produces 4895-like burn characteristics
2) The gas system could be clogged/obstructed or leaking. Remove the gas plug from the gas cylinder. Drop out the piston. Clean the cylinder and outside of the piston. The inside of the piston and gas plug can be cleaned with a tight fitting drill bit (turn by hand!). At this point you can run a pipe cleaner through the cylinder and up through the spindle valve and into the barrel. Reassemble with everything dry. Be sure and snug up the gas plug using a wrench or M-14 combo tool.
3) The M1A/M-14s really work best using grease, not oil as a lube. The M-14 FM shows where to lube, but in a nutshell: the op-rod, bolt roller (really force grease into it like you were packing grease into a wheel bearing), the ways for the oprod and bolt on the receiver, and the top of the hammer. I also like to put grease on the oprod spring guide.
4) As has been stated, the screw for the scope mount could be extending too far into the receiver. You should be able to see that visually, but you can check for other binding by removing the oprod spring and manually cycling the action.
5) Try a different magazine.
If I had to guess, I would bet on a gas leak (loose gas plug) or in need of lube... or a combination thereof.
Nearnuf
Thanks for all the replies.
I am using Lithuanian Nato surplus that I have always used with this gun. I have also tried some Remington hunting .308 with the same results.
I have cleaned and relubed with tetra grease and Royal Purple motor oil.
Tried several magazines including a new CMI mag.
I looked at the screws on the scope mount. They do not appear to protrude into the reciever but I suppose that they could distort the reciever if torqued too tight.
I did check the spindle valve and even fired a round on the grenade launcher setting. That may have been a mistake. It did result in a failure to eject and I had to pound the shell out with a cleaning rod.
One thing I have not tried is to get something up through the port between the barrel and the gas system.
So basically you are saying that the problem hasn't been corrected. Did you make any other modifications? Extra power Wolff springs or anything? Did you always clean the weapon after you fired it? Was it working fine the last time you fired it and then put it into storage?
Thanks for all the replies.
I am using Lithuanian Nato surplus that I have always used with this gun. I have also tried some Remington hunting .308 with the same results.
I have cleaned and relubed with tetra grease and Royal Purple motor oil.
Tried several magazines including a new CMI mag.
I looked at the screws on the scope mount. They do not appear to protrude into the reciever but I suppose that they could distort the reciever if torqued too tight.
I did check the spindle valve and even fired a round on the grenade launcher setting. That may have been a mistake. It did result in a failure to eject and I had to pound the shell out with a cleaning rod.
One thing I have not tried is to get something up through the port between the barrel and the gas system.
That you had to hammer the case out when you had the spindle valve off does not seem quite right... have you cleaned the chamber with an M-14/7.62 Chamber Brush?
Nearnuf
When was the last time you pulled the gas cylinder and plug and reamed out the carbon? You should try to do that every 300 rounds.
Do you hear it click-clack when the bolt is locked to the rear and you raise and lower the muzzle?
No modifications. I don't think I've had 300 rounds through it since I bought it. In the case of the failure to eject - I did clean the chamber out with a ratcheted chamber brush after this occurred so that could have been a dirty chamber. I had cleaned the gun after every firing but I hadn't ordered the chamber brush until recently. Failure to feed persists after chamber cleaning.
I hadn't fired the rifle between the time I had the mount and scope installed and when I put it in storage. At this point the smith job was about a year ago and in another state so if it comes to that I will be going to another smith.
I will do a pipe cleaner (or whatever I can find around the house) through the gas port tonight but I will not be able to get out to the range to test the results until this weekend.
I will also try the raise and lower the muzzle thing tonight. I assume that I want to hear the click?
Correct. That will be your gas cylinder going back and forth under its own weight.
Remember to lock back the bolt and op rod.
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