New M305, Q about indexing and a few other things.

So made a trip to Hungry's today to get my indexing straightened out. Ended up doing a bunch of other things too while we were at it. Didn't think I could learn so much in a couple hours! As it would turn out, my 305 is actually in pretty good shape. Op rod guide was nice and tight (dimpled it anyway), gas lock turned out to be pretty well perfect as far as tightness. We ended up securing my gas cylinder by giving some good hits to the edges of the spline channels using the edge of a hammer. Flash hider came off with no issues and the welds were cleaned up. Securing method for the gas cylinder was applied to my flash hider. The reindexing went without a hitch and I even got to help unscrew the barrel of a remington 700 from the receiver. Here's some pictures from this afternoon and after I reassembled my rifle tonight:

In all her dismantled glory
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Dimpled the collar where the op rod guide slides onto. Used a hammer and center punch. Like Hungry says, hit it like man! No loctite was required. Note that dimpling should be done on either side of the pin groove also!
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Welds from the flash hider to be filled down:
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The feed groove after re-indexing:
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One of the most important things I learned today was not to be afraid with going near these things with hammers :D A rubber mallet is your friend for removing and reinstalling various parts. Of course masking with tape is never a bad idea for steel on steel contact!
 
Dling said:
So made a trip to Hungry's today to get my indexing straightened out. Ended up doing a bunch of other things too while we were at it.

Dimpled the collar where the op rod guide slides onto. Used a hammer and center punch. Like Hungry says, hit it like man! No loctite was required. Note that dimpling should be done on either side of the pin groove also!



Welds from the flash hider to be filled down:


The feed groove after re-indexing:

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Click to expand...

That rear aperture hole looks bang on. Is it the OEM Norinco or USGI/SA/PB?
 
It's OEM Norinco. Everything on my rifle is OEM for the moment. I probably won't ever end up replacing the rear aperture since I plan on mounting a glass piece on it eventually with a CASM mount.
 
oh... what have I gotten myself into... I have no idea how to check indexing (new to the sport) and just received a norc m305 yesterday... any one around lethbridge alberta that you know that can check and show me how to fix/maintain mine properly?
 
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Not that hard to check indexing. Look at the feed ramps. That little triangle shaped notch should be in the center, or if you look at the barrel/gas cylinder, They should be inline with each other. Front sights will look crooked too. If you look at the first page of the thread, Chalkriver uploaded some really good pics showing the process of re-indexing. I'm far from an expert however, as I'm brand new to all this stuff too. Hungry and 45ACPKING are pretty much the experts when it comes to theses things. Keep in mind, there's not really anything unsafe about improper indexing as far as I know, but it's annoying to look at. It's a battle rifle, they're meant to work in the worse of conditions :D.
 
Could you see if my indexing is okay?

Pics of the chamber, front sight, and muzzle/gas cylinder. The gas lock has been unscrewed so it doesn't line up perfectly in the pictures.

Just based on Dling's photos after Hungry worked on it, my triangle feed ramps in the chamber look ok. I think looking from the muzzle it's okay too. The front is slightly drifted to the right when looking from the receiver, but it's level.

Let me know what you guys think. Thx :)

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You have at least 3 things that "index" to the receiver. The feed ramps, then the gas system, then finally at the muzzle, the front sight. Since the machining of the splines on the barrel, and the parts that hang from them have some chinese manufacturing tolerance to them, its a juggle as to which one should be brought to near perfection. I'd say go off the front sight initially, and see if that puts the others into an acceptable, functioning position. You could either use your front sight (which may be improperly machined, and thus crooked to index off), or the muzzle end of the barrel's machining and its splines.
 
I found this post by Lazerus (he contributed to the stickies above before being banned) on indexing. He says that you should look at op rod tip alignment to the gas assembly as the front sight and flash hider can appear canted due to manufacturing variances.

''Before you go cranking the barrel around, check a few other things for alignment.

Since you are a Canuck, you should know that the [very popular in Canuckistan] Chinese 14s are well supported by the Canuck web sites. Canadiangunnutz and Canadiangunslingers. Both sites have detailed DO-IT-YOURSELF stickies and even some videos that deal with the Chinese 14s quite thoroughly. Most Americans have much less experience with the idiosyncracies of the CHINES 14s, as they are used to the much more common [for them ] US built M14 clones.

While out of index barrels are quite common on the later built Chinese built M14 clones,
they also have various other issue that show up as the same symptom.
Also some times seen are;

- front sight dove tail and top of base milled at an angle which tilts the front sight

- flash hider lugs milled out of alignment, which rotates the entire flash hider

HOWEVER,
the fact that you also have the op rod guide out of alignment enough to contribute to op rod binding probably indicates that the barrel IS out of index. To check alignment on your rifle, I suggest you go by the GAS ASSEMBLY to op rod tip alignment rather than the front sight or the feed ramps. If the tip of the op rod indexes correctly with the tail of the piston, your op rod guide is in the right place for the gas assembly.
BUT,
If you still get op rod binding when the tip and the tail are aligned correctly, then either the grooves in the gas cylinder mount are rotated out of alignment for correct op rod TAB to receiver alignment, or the op rod is bent. If the grooves that mount the gas assembly are out, then your barrel is definitely mis-indexed.

SO, find some local professional [ DLASK or Barry @ Bits of Pieces ] have the proper barrel and receiver tools to reindex an M14.

If you can find the tools and want to attempt to do-it-yourself [ I've taught dozens of people how to do this ] it does not have to be a big deal.

UNDER indexxing is better than OVER indexxing, as you simply have to tighten the barrel a bit. Just remember to remove that little barrel retaining screw under the op rod [ USE AN IMPACT DRIVER AND A PROPER FITTING HARDENED BIT HERE ... OR ELSE!!! ] before attempting to tighten down the barrel. For this simple job, don't get too complicated and worry about torque or head space changes .... the barrel shoulder is undercut and tapered so will actually "CRUSH" into place when turned. Go for correct alignment, and don't worry about anything else. Tightening the original barrel a few degrees will actually improve the head space very slightly on the notoriously long chambered Chinese 14s.

If your barrel had been OVER indexxed, then things would get more complicated. With over indexxing, you need to remove the barrel completely and either roll the shoulder back down for correct "DRAW/TORQUE" or carefully peen it back into place with a thousand little hits by a teensy tiny hammer. THEN you need to worry about torque and draw etc.

Good luck with that,
LAZ 1
[;)''
 
Not to thread jack, but I just received my 22" from Lever Arms, and everything looks pretty good, like your's.
The only thing I may need to do is take a file to the mag release (it's really, really tight) and shim the gas lock (it's loose at the 6:00 position, and only becomes tight at the (9:00 position).

The 18.5" I purchased late last year was really poorly put together but Hungry helped me sort that all out and now I'm happy with it.
(re-indexed, peened the op rod guide boss on the barrel and peened the spines for the flash hider and gas cylinder ring, replaced the front and rear sights and the flash suppressor).
 
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Odd shot seeing as you have taken a flash hider off already .... Remove the flashider on the 22" then take the gas locking ring off and turn it around and put it back on as this can sometimes cure your problem without the need for shims.
 
mosinmaster said:
What's the best way to loosen the castle nut if you don't have castle nut pliers? Soak with penetrating oil and ?
Click to expand...

You'll need the castle nut pliers. I tried without and mucked up the finish on the castle nut for absolutely zero progress
 
chalkriver said:
Odd shot seeing as you have taken a flash hider off already .... Remove the flashider on the 22" then take the gas locking ring off and turn it around and put it back on as this can sometimes cure your problem without the need for shims.
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Yup. Just gotta get around to this (need a sturdy workbench)
 
mosinmaster said:
What's the best way to loosen the castle nut if you don't have castle nut pliers? Soak with penetrating oil and ?
Click to expand...

You have to remove the setscrew holding the castle nut before turning the nut.
You can fabricate the pliers from hook nosed vice grips.
 
mosinmaster said:
What's the best way to loosen the castle nut if you don't have castle nut pliers? Soak with penetrating oil and ?
Click to expand...

Order a pair of pliers. I made a small attempt with a punch and hammer on one of the castles and it didn't even budge. Hungry ended up taping the flash hider back TOWARDS the receiver to loosen up the nut since even the proper pliers wouldn't do it at first.


I'll be getting to the range sometime this weekend hopefully and I'll post up some groupings after. Got a USGI spec op rod spring coming in the mail and a Sadlak spring guide collecting dust right now, so I can hopefully throw up some comparisons after. Assuming I'm not too embarrassed with my shooting of course :redface:
 
toyboy said:
You have to remove the setscrew holding the castle nut before turning the nut.
You can fabricate the pliers from hook nosed vice grips.
Click to expand...

one could, but I found it easier to just buy the pliers. They're like $15, or something like that.
 
Can someone show me reference material that is telling you guys to use the feed ramps as an indicator for indexing?
I've indexed 100's of these rifles and feedramps were not part of the equation.

First thing a guy should do if he suspects an index issue is examine the flash hider first. Is it offset to one side? Does it have a tipped or offset sight base?
Inspect front sight, is the blade or ears bent or uneven?

Forget about binding oprods and feed ramps.
The gas port is the barrel"s dimensional zero.
Splineways, hand guard slots, barrel shoulder, barrel threads, chamber face ect are all measured from the barrels zero, the gas port.
If you get creative, you can "map" your barrel, without any parts on it, to tell you if splineways are off ect.

Now if you suspect it might be the flash hider and not the barrel... Get rid of it. Pm spcammno for a springfield or try treeline or the EE. Get a flash hider you know was made right.
Then, use the helpfull tips from Skullboy in the "stickies", where he shows the alignment bars used for indexing.

Indexing has a allowable tolerance of +/- 3degress off top dead center, either way. This allows for the minor variances that may be found in quality flash hiders.
By tightly fitting the new flash hider, or one that is known to be acceptable for use, and setting the alignment bar on top and one behind rear sight, indexing becomes very easy to eyeball.

There's no voodoo magic or rocket science here. It's a simple thing made complicated by crappy chinese flash hiders and the need for certain tools to do it yerself.
 
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