M-1A/M-14 gas system - just learned about the external "Spindle Screw"...almost planned to take rifle to gun smith. Relief !

I

Ignition Override

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Yesterday drove my typical 1:20 to a very long rifle gully at the Second private club I belong to.

The M1A had a mix of its very First anomalies and malfunctions. So bizarre after shooting over 400 trouble-free rounds in this 2022-vintage S.A. M1A Standard. :scrutiny:No ****** idea how the “screw” (which allows or blocks gas flow) got misaligned. So bizarre.
This video explains to ensure that your spindle screw's Slot is Vertical:eek:. If it is parallel with the barrel and gas tube the gun no will work--unless one's gun is suppressed or You Gots Grenades and a launcher.....

.....sidenote: .It has the same function as the small external gas selector knob —forward—of the FAL rifle's sights.
What a relief today having a functional M1A after simply pushing the screw inwards and turning it. Very simple.

Wrong position in video at 2:24.
Correct alignment at 3:51.

As a side-by-side contrast for normal people, or especially for those professionally--cynical people who believe that most gun advice on the Internet is mistaken…..
Photo from whichever M1A / M-14 Owner's Manual is at 4:55.

www.youtube.com

New M1A / M14 Won't Cycle, What to do

The solution to this issue is truly this simple. 99.99% of the time, if your new M1A or M-14 won't cycle properly and the ammunition is correct. The Spindle...
www.youtube.com www.youtube.com
 
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Even a former coworker who sometimes competed with M-14s (but mostly ARs, some Garand) on the Navy Rifle Team did not remember that critical "screw" when I asked him yesterday about malfunctions.
They likely had no issues with their rifles, whether supplied by Crane Logistics or they were personal guns.

The guy who created the video received many peoples' thanks.

Maybe M-14 Forums has a "malfunctions Stickie list" but I didn't think to look. Another guy on that forum has no idea how his screw ever got rotated away from the vertical slot setting.

GRIZ22: A local Memphis gun smith (super nice, did a few small "tweaks" with no charge/ I gave him free ammo) might have been less fortunate to have gone through basic around '67 or so. He was in the Army iirc
He told me that he was infantry in Vietnam. Just the sad look on his face (with no other words) kept me from asking any questions.
 
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Ahhhh...gas shutoff valves, such fun!
Of course Yugo SKS are famous for eroded valves causing cycling problems. On the M70B (AK), flipping up the grenade sights would also cutoff the gas supply. Can't have those conscipts blowing themselves up by firing a live round into a freshly launched grenade now.....
Probably a good thing rifle-grenades have largely fallen from favor. Always thought the shoot-through models were kinda funny.

My M1A never flipped the valve by itself, but I did use it as a manual repeater a couple times to keep brass from hitting shooters to my right.
 
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Several years ago I did one of my science experiments. I loaded with great care 20 rounds of .308 Winchester. I fired ten over the chronograph and then turned the gas off and fired the remaining ten over the chronograph. Interesting because I expected the manually cycled rounds to have higher velocity. The difference was not really noticeable. Next I measured the cases and the before and after was the same on all the cases. I was totally familiar with the gas system and rifle since my first was an M14 compliments of the Marine Corps. :)

Ron
 
If the rifles had a pair of red dots (markings) at 12 and 6 o’clock to indicate correct vertical alignments for the subtle slot, somewhat like on the FAL’s gas plug (Imbel style) then maybe most people would be aware of, or curious about it.
 
Way back in the dark ages I replaced a POS M16 with an M14. The fellow the the EGA who traded it to me (the USAF had better tasting beer), gave me a pretty good run down on how it operated and how to maintain it. Out of curiosity, I played with that part and quickly learned to it it and not mess with it.
 
NIGHTLORD40K said:
Ahhhh...gas shutoff valves, such fun!
Of course Yugo SKS are famous for eroded valves causing cycling problems. On the M70B (AK), flipping up the grenade sights would also cutoff the gas supply. Can't have those conscipts blowing themselves up by firing a live round into a freshly launched grenade now.....
Probably a good thing rifle-grenades have largely fallen from favor. Always thought the shoot-through models were kinda funny.

My M1A never flipped the valve by itself, but I did use it as a manual repeater a couple times to keep brass from hitting shooters to my right.
Click to expand...
How about the bullet trap design.

image001.gif
 
Carl N. Brown said:
It is called a "spindle valve" not really a screw.
It was designed to be depressed and turned with a cartridge rim.
Most people ignore them until they are totally frozen in place.
Click to expand...
Not really an issue unless you're shooting rifle grenades.
 
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