Results 1 to 18 of 18

Thread: M1A Gas spindle valve

  1. #1
    Chief
    Follows
    0
    Following
    0
    BattleAxe's Avatar
    Join Date
    Mar 2010
    Location
    NE Florida
    Posts
    1,176

    M1A Gas spindle valve

    Any of you guys use it such as when firing suppressed? Someone told me once not to touch it on a match gun and as such had largely forgotten it was there, but it seems like it would be a very handy device. Any issues I should be aware of here? Any problems with case extraction?
    Just be glad I'm not your kid.

  2. #2
    Sergeant
    Follows
    0
    Following
    0

    Join Date
    Oct 2009
    Location
    Ohio
    Posts
    224

    Re: M1A Gas spindle valve

    I was told that if you open it so the gas system will not function it will harm the rifle. I do not know if it is true but after taking the time to properly accurize my rifle and bed it in a McMillan stock with a Heavy Kreiger I didn't want to experiment.

  3. #3
    A never was has been
    Follows
    1
    Following
    0
    gunfighter14e2.'s Avatar
    Join Date
    Jul 2002
    Location
    Lickskillet Alabama
    Posts
    0

    Re: M1A Gas spindle valve

    Do not turn the gas off, unless your launching grenades or shooting a line throwing device.

    Most all M14's or M1A's I've turned the gas off, will lock the bolt up until the weapon cools or you kick the op rod with you boot. If you get to shooting subsonic ammo threw a can, yes you then can turn it off.
    Many a XM21 was turned on an off, when subsonic ammo was used, but that was the only time, (save, line and grenades).
    After a hard day on the net or at work, be sure to have a bottle of BLR at the ready to remove the taste from all that polished leather.
    Boot Licker Relief, the discriminating mouth wash for those who live on their knees.

    Duty, Honor, Country.
    Three words most never fully understand, their whole life

  4. #4
    Gunny Sergeant
    Follows
    0
    Following
    0
    samnev's Avatar
    Join Date
    Mar 2010
    Location
    Prescott, AZ
    Posts
    2,817

    Re: M1A Gas spindle valve

    If I'm not mistaken the gas valve on the Match M1A's are pinned and can't be turned. At least it is on mine which is a Devine TX one. Don't know about GI M 21's

  5. #5
    Gunny Sergeant
    Follows
    3
    Following
    0

    Join Date
    Apr 2002
    Location
    Park City, Utah
    Posts
    1,513

    Re: M1A Gas spindle valve

    M21s and AMU National Match M14s had the gas cutoff epoxied in the "Open" position.

  6. #6
    Private
    Follows
    0
    Following
    0

    Join Date
    Dec 2009
    Location
    Las Vegas, Nevada, USA
    Posts
    55

    Re: M1A Gas spindle valve

    If you're shooting a M14 type rifle with a suppressor but it doesn't have a scope mount over the receiver, you can use the M3 breech shield to deflect the blowback. I've tried this. It works well.
    Salus Populi Suprema Lex Esto

  7. #7
    Private
    Follows
    0
    Following
    0

    Join Date
    Jun 2010
    Location
    Texas
    Posts
    15

    Re: M1A Gas spindle valve

    cool

  8. #8
    Gunny Sergeant
    Follows
    0
    Following
    0
    MK14 SEI's Avatar
    Join Date
    Feb 2009
    Location
    US
    Posts
    1,096

    Re: M1A Gas spindle valve

    Originally Posted By: Different
    If you're shooting a M14 type rifle with a suppressor but it doesn't have a scope mount over the receiver, you can use the M3 breech shield to deflect the blowback.
    I've tried this. It works well.


    [img]<>/smile.gif[/img]

    Agreed.

    M3 on the right.





  9. #9
    CMP GSM MI
    Follows
    1
    Following
    0
    kraigWY's Avatar
    Join Date
    Feb 2006
    Location
    Wyoming
    Posts
    2,089

    Re: M1A Gas spindle valve

    Quote:
    If I'm not mistaken the gas valve on the Match M1A's are pinned and can't be turned. At least it is on mine which is a Devine TX one. Don't know about GI M 21's


    Santo, that's the way they are suppose to be. M-21s are NM Rifles, they have the gas valve locked where they can't be turned. They were that way on all the M-21s at the AMU Sniper School, and the M-21 systems my state (NG)were. I have the manuel for building NMs from M-14s and it covers locking the gas valve. I've seen a lot of M-21s and NM M-14s and I never saw one that wasn't locked.
    Kraig Stuart
    Distinguished Rifle Badge #1071
    USAMU Sniper School, Oct '78


  10. #10
    Gunny Sergeant
    Follows
    0
    Following
    0
    samnev's Avatar
    Join Date
    Mar 2010
    Location
    Prescott, AZ
    Posts
    2,817

    Re: M1A Gas spindle valve

    I was aware that they were supposed to be pinned on the commerical M1A match rifles I just wasn't sure about the M21 since I never handled one although I was pretty sure they would be pinned as well. Thanks for the feedback.

  11. #11
    Gunny Sergeant
    Follows
    0
    Following
    0
    RollingThunder51's Avatar
    Join Date
    Feb 2009
    Location
    U.S.A.
    Posts
    1,582

    Re: M1A Gas spindle valve

    ..

    Some can providers will custom machine a spindle to allow for the use of the switch as the means to properly provide for suppressor function. The process begins with the host being sent in. The result is as good as it can get for this action.

    ..

  12. #12
    Gunny Sergeant
    Follows
    0
    Following
    0
    MK14 SEI's Avatar
    Join Date
    Feb 2009
    Location
    US
    Posts
    1,096

    Re: M1A Gas spindle valve

    Originally Posted By: RollingThunder51


    The result is as good as it can get for this action.



    What is the result?


  13. #13
    Gunny Sergeant
    Follows
    0
    Following
    0
    RollingThunder51's Avatar
    Join Date
    Feb 2009
    Location
    U.S.A.
    Posts
    1,582

    Re: M1A Gas spindle valve

    ..

    That which you already are very much aware of. Mechanically, the action creates a good deal of mechanical noise. What is accomplished is flawless cycling, appropriate gas pressure and safe bolt function. The ability to remove the can and return to proper un-supressed function. All of that while maintaining excellent accuracy.

    The spindle work accounts for the relative sensitive balance between action reliability and safety when suppressed. As an example, a properly prepared spindle was provided for a customer provided host, when the owner received the unit, he chopped the barrel back only to find the accuracy and cycling suffered when suppressed. A new spindle was required, provided and the issue was resolved. The new can is 100% titanium, weighs about 15 oz and is quieter than.....right...the action.

  14. #14
    Gunny Sergeant
    Follows
    0
    Following
    0
    MK14 SEI's Avatar
    Join Date
    Feb 2009
    Location
    US
    Posts
    1,096

    Re: M1A Gas spindle valve

    Well, I currently enjoy flawless cycling, appropriate gas pressure and safe bolt
    function plus the ability to remove the can and return to proper un-suppressed function.


    Will the modified spindle you speak of cycle sub sonic ammo?


  15. #15
    Private
    Follows
    0
    Following
    0

    Join Date
    Jan 2010
    Location
    Pennsylvania
    Posts
    43

    Re: M1A Gas spindle valve

    The gas spindles on the earlier M21's and National MAtch Rifles were not epoxied opened but rather the process of unitizing the front ferral and the gas tube was to drill though the ferral into the gas cylinder and finally into the gas spindle. The spindle was then tapped and two nylock screws were used to lock the ferral, gas cylinder and spindle together making the gas system unitized and more accurate.

    Later the units were simply tig welded (AMU) across the top and bottom of the gas cylinder. These units the spindle will rotate.

    I have fired the rifle with the spindle closed. I never had any problem with it.

  16. #16
    Gunny Sergeant
    Follows
    0
    Following
    0
    RollingThunder51's Avatar
    Join Date
    Feb 2009
    Location
    U.S.A.
    Posts
    1,582

    Re: M1A Gas spindle valve

    H20, most think they have safe pressures, most think their bolts are not slamming. Most confuse always cycling with safe cycling. Not saying you aren't, not at all. But, it takes more than a spoonful to get it right with cans on M1a. On this host, back pressure can wreck the extractor. With a tuned spindle set (can/spindle) the tuning is based on back pressure testing. Can off? Just rotate to norm.

    Subs? Probably not, if it is cycling on yours, well there you go..excess pressure..enough to cycle on subs..ng. Can be tuned for JUST subs and can off but not sub, normal suppressed, no suppressor.

    I too have had no issue shutting off the gas. On the FN FAL as well. There the gas port is welded and drilled to .06 or .07 to be "in range" for the normal adjuster tuning.


  17. #17
    Sergeant
    Follows
    0
    Following
    0
    Mr blasty's Avatar
    Join Date
    May 2010
    Location
    MN
    Posts
    0

    Re: M1A Gas spindle valve

    Originally Posted By: M25BeastShooter
    The gas spindles on the earlier M21's and National MAtch Rifles were not epoxied opened but rather the process of unitizing the front ferral and the gas tube was to drill though the ferral into the gas cylinder and finally into the gas spindle. The spindle was then tapped and two nylock screws were used to lock the ferral, gas cylinder and spindle together making the gas system unitized and more accurate.

    Later the units were simply tig welded (AMU) across the top and bottom of the gas cylinder. These units the spindle will rotate.

    I have fired the rifle with the spindle closed. I never had any problem with it.


    Correct except The marine corp is the one that came up with welding them. The "screw and glue method" is the AMTU method.
    Originally Posted By: Kbrady
    It's time for criminals that mean to do us harm to end up on a cold slab. In the time it takes them to be arrested, bailed out and back on the streets, they could be in the peak stages of rigor mortis. Fuck em.

  18. #18
    Gunny Sergeant
    Follows
    0
    Following
    0
    MK14 SEI's Avatar
    Join Date
    Feb 2009
    Location
    US
    Posts
    1,096

    Re: M1A Gas spindle valve

    Originally Posted By: RollingThunder51



    Subs? Probably not, if it is cycling on yours, well there you go..excess pressure..enough to cycle on subs..ng.

    Roll, I've never had an M14 that cycled subs and that's a good thing because factory sub-sonic ammo is expensive [img]<>/wink.gif[/img]


    Quote:

    ...most think they have safe pressures, most think their bolts are not slamming. Most confuse always cycling with safe cycling.


    Yeah, I'm glad I don't have to be concerned with any of those issues.