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Feeding problems with M1A

Discussion in 'Rifle Country' started by uneasy_rider, Dec 18, 2007.

  1. uneasy_rider

    uneasy_rider New Member

    I can hand cycle rounds through my M1A with no problem. However, I am having trouble when shooting. Sometimes, the spent cartridge is not ejected from the rifle at all. I don't think the bolt even opens when that happens, but its hard to tell. Sometimes, the spent case is ejected, but a new round is not fed into the chamber. I can't tell if the bolt is going back far enough to pick up a new round. I think it might be short stroking. About 20% of the time, it will eject a spent case, and pick up a fresh round like its supposed to.

    This was the first time I have shot this rifle in over a year. I have never cleaned the gas system, but have field stripped the rifle and cleaned it when I put it up last year. It has about 500 rounds max through it, and has never had a cycling problem til now. I am using USGI magazines.

    What is my problem?
  2. Andrewsky

    Andrewsky New Member

    What ammo are you shooting?

    Do you have a scope mount?

    What make is your extractor?

    Is your gas valve completely in the open position?

    Clean your gas system.

    What kind of lubrication are you using?
  3. uneasy_rider

    uneasy_rider New Member

    I am shooting reloads that work fine through my FALs. They are 150g FMJ's loaded over 43.5g of Winchester 748, to give a chronographed velocity of 2600 fps.

    I know people poo poo reloads here, but these are well made and I do not believe are part of the problem. I plan on trying some Winchester 7.62x51 NATO surplus over the weekend, but don't expect it to make any difference.

    My extractor is whatever Springfield Armory puts on their M1A's.

    I am not sure what position my gas valve is in. The gun worked flawlessly the last time I used it, which was over a year ago. How do I tell what position it is in ?

    I lubed it when I put it up a year ago, using Lubriplate.
  4. Andrewsky

    Andrewsky New Member

    The valve should be straight up and down; perpendicular to the barrel.

    Try out that NATO stuff.

    Springfield extractors are notoriously bad. You might have to replace yours with a Fulton extractor. They're $35 but Fulton is having a 12% off sale right now. You can use the M14 combo tool to take the bolt apart. Degrease the gun and apply tetra grease.

    And clean your gas piston, but do not lubricate it. Make sure you have the appropriate tools for disassembling the gas system so you don't put any torque on the barrel, etc.
  5. uneasy_rider

    uneasy_rider New Member

    What tools do i need to disassemble the gas system?

    I have heard lubriplate is what the military uses to lube the M14. Do you think Tetra is better?
  6. Slugless

    Slugless Member

    I suspect it's your gas system.

    Pick up the rifle, hold it in the vertical position muzzle up. Now flip it over so the muzzle faces down.

    Does the gas piston move freely? If it doesn't move it badly needs cleaning.

    That said, I have a similar problem with my M1A. With Lithuanian ammo, it ejects fine but seems to be short stroking - either failure to feed or failure to go into battery.

    I cleaned the piece and cleaned the gas system well (even though the piston moved) with q-tips and scotchbrite. Also I tightened up the gas plug real well, it wasn't torqued properly. This reduced the FTFeed to 5% from 20%.

    I then ordered gas system cleaning materials from Sadlak Industries. Nice kit.

    I've not shot it since because of the deer season rush at the rifle range. Lots of yahoos & distractions. I plan to shoot it over the holidays.

    For me it seems to be a combination of ammo + dirty gas system. My rifle also had sat around for a couple years & when I brought it out it seemed over lubed.

    There's some other things to look at, too but first:

    *clean the rifle
    *use lubriplate only on the parts of the rifle where it is specified
    *clean the gas system thoroughly w/drill bits, don't lube it at all
    *check the gas valve - the slot in it should line up in the same direction of the gas flow
    *check the gas port in the barrel for obstructions
    *try some different ammo
    *search on M14-forums for similar problems (you'll probably find my post)

    Let us know what happens.

    *Edit - whoops, other posts in the meantime. Tetra is excellent, I highly recommend it. I use Tetra, not lubriplate. Use the combo tool on your gas system.
  7. uneasy_rider

    uneasy_rider New Member

    I can hear the piston moving when I have the bolt locked back, but not when the bolt is forward. Is that normal?

    Where can I get detailed instructions on how to clean the gas system?
  8. Slugless

    Slugless Member

    {deleted. that was so stupid I'm embarrassed. RTFM.}

    Send me a PM for some cleaning instructions.
    Last edited: Dec 18, 2007
  9. GunTech

    GunTech New Member

    The piston should move with the bolt back, and bolt when the bolt is forward. Perfectly normal. When the bolt is forward, the op rod is resting against the piston.
  10. GunTech

    GunTech New Member

    To disassemble the gas system, you need a combo tool or a 7/16 wrench. Just unbolt the gas plus and the piston should fall right out. I use a set of Sadlak drills to get to crud out.

  11. GunTech

    GunTech New Member

    Are you using commercial or military brass? In military brass, 43.5 should give about 2740 fps (LC). In commercial brass like WW, you need to kick it up a couple of grains.

    Try this: Insert one round in an empty magazine and fire. Does the bolt lock open?
  12. W.E.G.

    W.E.G. Active Member

  13. Z71

    Z71 New Member

    When the bolt is foward in battery on an M14/M1A rifle, the op-rod is forward against the gas piston. Have to lock the bolt back to hear the gas piston clunk back and forth when checking for a stuck piston.

    I've had my Polytech M14S rifles work fine with the gas piston stuck enough that it wouldn't move under it's own weight.

    Almost sounds like a blocked or mis-aligned gas port. Better check out the gas valve setting, and possibly the assembly of the gas piston housing and retainer parts.
  14. Slugless

    Slugless Member

    Here's some advice I received:

    Does anyone know the best drill bit size? Or another method/alignment gauge?
  15. Wild Deuce

    Wild Deuce New Member

  16. uneasy_rider

    uneasy_rider New Member

    I am using once fired Lake City military brass bought from GI Brass and sized with RCBS small base dies. I get an average of 2600 fps from both the M1A and the FAL. I am loading to an OAL of 2.800", which is about maximum length that will fit in the magazines.

    Do you think 2600 fps is too slow to cycle the M1A mechanism?
  17. GunTech

    GunTech New Member

    That load should run. Do you have the same issue with all magazines? Have you tried milsurp ammo?
  18. Andrewsky

    Andrewsky New Member

    Make sure that when you take your gas piston out you don't drop it on a hard surface.
  19. Winger Ed.

    Winger Ed. New Member

    Darn, that's frustrating.
    I thought the gas piston thing would have gotten ya fixed up.
    If ya can hear it sliding back & forth- with the bolt open- its fine;
    and I wouldn't take it apart if it was mine.

    You're doing everything right,
    and your ammo is plenty hot enough to make it cycle.

    The only other 'shot in the dark' I can think of is your magazine
    just 'doesn't fit'.

    Can ya get, and/or try- a real, genuine, un-damaged, clean, black, USGI magazine for it,,
    and not just another after market one?

    (I've had the gray or silver aftermarket M14 magazines just give me fits--
    Right up until I put them up on top of the target board and shot them with
    a .50BMG----several times)

    If the feed lips on top of the mag. are screwed up:
    they'll present the next round improperly to be fed into the chamber,
    and maybe even drag on the bottom of the bolt.

  20. Chris Orndorff

    Chris Orndorff New Member

    I had a similar problem with my M1A; failure to extract. My rifle was clean, properly lubricated and the gas system was clean and dry. I had a GI extractor in the bolt. I finally sent the rifle back to SAI and they replaced the bolt with a forged item. It's run perfectly since then.

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