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

We have the ranges booked for Oct 19-20 ....so those are the tentative dates so far.
We have to wait for confirmation from Range Control .
I will be starting a thread in the Events and Gatherings section once things firm up.
Hungry will hopefully coming up to Petawawa for 3 different types of clinics this year (CQB, Precision and M-14) :dancingbanana::dancingbanana:
So Odd Shot you had better get those Arms 22 rings sorted out and tested....lol
 
Dling you over timing looks about exactly like on mine based on the windage added to your front sigh and the factory staking on the front sight for zero. Mine works fine, it is an annoyance when you are aware of it, but unless you are going way out with iron sights 400,500, 600etc, you wont notice anything here. If Hungry can take care of it for you, that will be the best bet. Mine would have been done if I could have attended his clinic our way last year.

They(Norinco) know they over tightened alot of these barrels, evident by the factory windage adjustment and staking, but why not tighten it properly?

The only logical reason I can think of from a production stand point is this,..... they are trying to get the rifle into a "safe head space" dimension, by using the fastest and cheapest way available to them,..drive the barrel in further closer to the bolt face!
 
I'll be driving out to see Hungry Saturday to pass my rifle off to him so I won't have to worry about that anymore in a weeks time. The changing in headspace dimensions is an interesting thought though. Should I get it to a gunsmith to get it checked with a go/no-go gauge after Hungry resets the barrel?
 
Dont worry about it...Bring a couple empty casings with you that were fired from this rifle and Hungry can measure the headspace of your rifle from them.
It will only increase a tiny bit when he backs out the barrel.These are battle rifles designed to work with larger tolerances.
 
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I won't be able to get on the range for a couple weeks, so I won't have any casings for Saturday, but I've got a caliper sitting around somewhere so I'll just measure 'em up when I get a chance. I won't be reloading so I suppose I won't have to worry unless I see cases splitting in half or something. I need to drill it in my mind that guns like it rough as far as operating the things go. Still surprises me the amount of force required to operate them!

On a side note, greased it up, and put it back together just to get some experience with the thing (left the handguard off though):
img0829j.jpg


Working a lot smoother now.
 
My shorty has exactly the same problem.
The front sight is all the way to the left looking from the muzzle.
I'd like to get that fixed as well. it is really anoying to see that off.

Any plans for the clinic closer to the GTA?
 
By my math, you would have to over tighten the barrel by nine minutes on the face of a clock, to adjust out the close to 15 thou over spec length of the chamber of my rifle. Yet, it shoots well and accurate.
 
MiniMe said:
My shorty has exactly the same problem.
The front sight is all the way to the left looking from the muzzle.
I'd like to get that fixed as well. it is really anoying to see that off.

Any plans for the clinic closer to the GTA?
Click to expand...


If your front sight is leaning to the left while looking from the muzzle end your barrel is UNDER Indexed and needs to be tightened onto the receiver more.
The op,s rifle was over indexed and the barrel needs to be unscrewed from the receiver .
 
isn't the OP's picture taken from the muzzle?
Mine looks exactly like that, and if that means unscrewing it a little, I wonder how that would affect headspace as it is already somewhere between 1.641 and 1.646

chalkriver said:
If your front sight is leaning to the left while looking from the muzzle end your barrel is UNDER Indexed and needs to be tightened onto the receiver more.
The op,s rifle was over indexed and the barrel needs to be unscrewed from the receiver .
Click to expand...
 
MiniMe said:
isn't the OP's picture taken from the muzzle?
Mine looks exactly like that, and if that means unscrewing it a little, I wonder how that would affect headspace as it is already somewhere between 1.641 and 1.646
Click to expand...

The thread pitch is ten per inch. That means 100 thou per full revolution. Since there are 360 degrees in a full circle, every tun of 3.6 degrees moves the barrel a max of 1 thou. As some of these barrels are loose, and others extremely tight, and further tightening might simply be stretching or distorting the threads, I say a max of one thou change (assuming no distortion of threads) per 3.6 degree of indexing.
 
MiniMe said:
isn't the OP's picture taken from the muzzle?


The pics the op provided show that the barrel was screwed in to far (over indexed) , look at the feed ramps in the 2nd and 3rd pics.
The front sight was moved to the right on the sight base (veiwed from the receiver end) to compensate for this. If it was centered on the sight base it would look like it was leaning to the left (veiwed from the receiver end).
Click to expand...
 
Grizzlypeg said:
The thread pitch is ten per inch. That means 100 thou per full revolution. Since there are 360 degrees in a full circle, every tun of 3.6 degrees moves the barrel a max of 1 thou. As some of these barrels are loose, and others extremely tight, and further tightening might simply be stretching or distorting the threads, I say a max of one thou change (assuming no distortion of threads) per 3.6 degree of indexing.
Click to expand...

You guys are getting too intelligent on me! :D

It's all good! When I finish with yer rifle, yer #### won't fall off! :evil:

Cheers,
Barney
 
Grizzlypeg said:
The thread pitch is ten per inch. That means 100 thou per full revolution. Since there are 360 degrees in a full circle, every tun of 3.6 degrees moves the barrel a max of 1 thou. As some of these barrels are loose, and others extremely tight, and further tightening might simply be stretching or distorting the threads, I say a max of one thou change (assuming no distortion of threads) per 3.6 degree of indexing.
Click to expand...

Thanks for info Grizz, now we know what a slight un-indexing will do on head space adjustment, practically nothing in our rifles.
 
chalkriver said:
We have the ranges booked for Oct 19-20 ....so those are the tentative dates so far.
We have to wait for confirmation from Range Control .
I will be starting a thread in the Events and Gatherings section once things firm up.
Hungry will hopefully coming up to Petawawa for 3 different types of clinics this year (CQB, Precision and M-14) :dancingbanana::dancingbanana:
So Odd Shot you had better get those Arms 22 rings sorted out and tested....lol
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gah!!! yes, most definitely!!!


Definitely want to hit this workshop for sure!
 
How much do the courses cost?

And it's good to know my #### won't fall off, Hungry haha. Where did that saying come from anyway? I always see it around here.
 
Dling said:
How much do the courses cost?

And it's good to know my #### won't fall off, Hungry haha. Where did that saying come from anyway? I always see it around here.
Click to expand...

The courses will be $35 a day ( all 3 courses are 2 day events).....Its way under priced for what he is doing for us .
Once the dates firm up I will be posting the course info in the Events and Gatherings section on here.
 
chalkriver said:
The courses will be $35 a day ( all 3 courses are 2 day events).....Its way under priced for what he is doing for us .
Once the dates firm up I will be posting the course info in the Events and Gatherings section on here.
Click to expand...

K cool. Definitely seems like something one wouldn't want to miss.

chalkriver said:
And the " Dont buy one Buy two !!" expression as well :D
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I can see how these guns get addicting with all the tweaking and customizations out there :D

Couple more pictures:
Assembled minus the hand guard.
img0832n.jpg


Not entirely sure what too look for on the bolt lugs, does this look normal?
img0831ig.jpg
 
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