GLFS not indexing?

Davy Crockett

Davy Crockett

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Ok, maybe I'm missing something really obvious but I went to install my new front sight base I got from Bits of Pieces and it sits a few degrees to the right. I leveled the receiver first but I can't get the sight close to level. How do I fix this?
 
Read the stickies about barrel indexing as it sounds like your barrel needs to be tightened a bit....and you can go to one of Hungrys m-14 clinics...there are a couple of clinics you can sign up for now if you live in ontario
 
An eyeball test for barrel indexing is to strip the rifle as far as you can and look down the top of the receiver at the splines. They should look like they are in a straight line with the receiver top. As you look down the barrel, then look at the sight base. If it looks canted then you need to do some further checking. Take a small level and set it on the flat behind the rear sight. Then move it to the sight base. If the splines look straight and your level says out of level, then you may have a mis-machined sight base, fairly common with the Chinese stuff.
 
OR.....
Your gas assembly could be the culprit.
A great many chinese cylinders are machined wrong in that the mounting splines are not in correct position to the center of the gas plug hole/ barrel ring hole. I've run into this issue so many times, I won't use gas lock sights anymore. This situation is the main reason I started TIG welding a front sight base directly to the gas cylinder barrel ring.
 
Thanks for the replies guys.

I may not be thinking this through all the way but I don't see how barrel indexing would fix this issue? Since the sight base attaches to the gas block and barrel, re-indexing the barrel would simply turn the threads on the barrel, right?

The gas cyl & nut holds the sight base in place. To me it looks like I would need to change the position of the barrel horizontally relative to the gas assembly to fix this.

It would really suck if this won't work since I already bought the base and a NM sight. I suppose I could chop the bottom off of the sight base and like Thomas says, have it TIGed on the barrel.
 
The gas system is indexed on the barrel by splines. If the barrel is not screwed in correctly, not only will it be out, but so will the gas system. As Thomas says, it could be either. I guess this is a shorty, and there is not flat left on the end of the barrel to check level. How was the previous front sight for level?
 
What Thomas said X TWO

I use Barry's GRFS as a tool to index my shorty M14 barrels.
These are very precisely machined with flats that are TRUE and SQUARE.

If the sight base is off [ more than the slight bit of clearance around the OD of the gas plug and the ID of the GRFS ] then the gas assembly is off.

And if the gas assembly is off,
EITHER the splines inside the gas assembly are off
OR
the center line of the hole bored inside the gas cylinder is off at the front [ I have one of these FUGLY gas cylinders in my hands as we speak, bored with a very noticeable angle ]. Norc gas assemblies with the hole at the back bored off side are much more common.
OR
the barrel needs to be rotated a teensy bit [ VERY COMMON ].

If you can get a different gas assembly, try swapping that in first.
Otherwise a trip to the M14 DR is called for to have the barrel re-indexed properly and precisely.

like we keep saying over and over,
with the Norc M14 rifles, quality control can vary considerably
[;{)
LAZ 1
 
ah ok, I knew I was missing something about the indexing, it all makes sense now.

As far as I remember the OE front sight was ok but it was chopped in short order. I'll have a look at the gas block when I get home.

again, thanks to everyone for their input
 
Davy Crockett said:
ah ok, I knew I was missing something about the indexing, it all makes sense now.

As far as I remember the OE front sight was ok but it was chopped in short order. I'll have a look at the gas block when I get home.

again, thanks to everyone for their input
Click to expand...
1 last thing...
Is the ultimate front sight mod from M14Doctor;

100_1129.jpg

100_1131.jpg

100_1135.jpg


You will never have to worry about lossing zero when you strip your girl ;)
 
Well I took a quick look tonight. I can see that the hole where the gas cylinder plug goes in is not centered, if I had to venture a guess it's probably off just enough to account for the sight being off.

Is there a way to fix this?
 
swap the gas cylinder for one that is bored on center.

If you have more $$$ than brains,
I can sell you a USGI gas assembly that will be perfectly straight,
OR,
some one on the CGN EE might have a Chinese one that is just as straight for a lot less cost.
Post a WTB add there and see.
good luck
[;{)
LAZ 1
 
Brownells can sell you an SA cylinder for 90.00 i think. Swap your chinese spindle valve, but you would also need an M1A gas plug and piston
 
The spindle valve is shown in this pic ....it shuts off the flow of gases to the gas system from the barrel... it was designed so you can fire rifle grenades .....if you turn the valve sideways with a flat tipped screwdriver you make your rifle into single shot as you will have to #### it after each round is fired

100_1129.jpg
 
I just posted my USGI gas assemble for sale in the EE ....
SOLD in minutes ...
ho, Ho, HO!!!
[;{)
LAZ 1
 
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