is this a problem?

7

730win94

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this is as far as my bolt will close on my norc on a full length resized piece of brass. HRT bolt that came with the rifle the bottom surface of the bolt lug beneath the roller is at least .070 from touching the reciever :runaway:
Picture023.jpg
sorry for the crappy pic
 
I would say that's a problem. The bolt will need to be lapped a bit to fit properly.
I would try it with factory brass first, just in case the sizing die is out of whack.......
 
once fired federal brass sized in a RCBS die setup to the word of RCBS instructions trimmed to 2.0045" thanks for the help :) is it possible that using a lee shell holder with RCBS dies is causing this problem?
 
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730win94 said:
once fired federal brass sized in a RCBS die setup to the word of RCBS instructions trimmed to 2.0045" thanks for the help :) is it possible that using a lee shell holder with RCBS dies is causing this problem?
Click to expand...

As long as the shelholder touches the die firmly when FL sizing it shouldn't be a problem.
If the bolt was brand new it may not be a drop in affair and require lapping. I've seen this frequently with TRW bolts. The good news is you can lap until headspace is right where you want it.
 
Thats ALOT of lapping....you need to make up about 6 thou or more judging by the bolt position. I'd try a different bolt first. If its an old Norc without chrome, you could ream a wee bit with a pull through. You really need to check it with guages while the bolt is stripped to know for sure.
 
This is from the M14 FAQ section:

Bolt Replacement & Fitting.

This is for those who wish to swap in a USGI bolt.

NOTE: Use the proper Headspace Gauges to check headspacing throughout this procedure.

First, make sure it is a USGI bolt, and not a Springfield Inc. bolt.(A run of commercial S.A> bolts were recalled)

You might be lucky enough to not have to lap the bolt.Swap out the old bolt and install the new one without the op rod attached.Move the bolt back and forth in the reciever and see how it fits and locks up.If everything looks good, then put the rifle back together.Just to see the difference, replace the original bolt, and slide it back and forth, and see how it locks up.Odds are that the USGI bolt has a tighter fit.

Once the rifle is back together, cycle the action a few times to see if there is any binding,roughness, or sticking of the bolt.If there is, you will want to lap the lugs.When I did my bolt swap, if I let the op rod fly home, it took a good deal of effort to open the action.If this occurs, you will have to lap the bolt lugs.

To lap the bolt lugs, you will need 400 to 800 grit valve lapping compound(available at your local auto parts store).You will also need a Full length sized case and a rod (or pin punch) that will fit into the extractor hole.

NOTE: The bolt MUST be stripped in order to properly lap the lugs!!!!

Remove the op rod, op rod guide & spring. Install the stripped bolt in the reciever .Dab a little of the valve grinding compound on the rear of the lugs that bear against the receiver locking cutouts.JUST a little.Don't over do it with the compound. Now place the sized empty case in the action and slide the bolt closed. The case will keep the bolt centered with the bore when lapping the lugs. Insert the rod/punch into the extractor hole and rotate the bolt open and closed. You just lift the lugs up & down. Do this approximately 25 or so times. Stop and check frequently by cleaning off the lapping compound and working the bolt. The bolt should fully lock up without any binding or roughness. Repeat lapping as neccessary until the bolt opens and closes smoothly without any binding or sticking. You should be able to cycle the action easily.

If you reload, I would make up a few Dummy rounds and cycle them through the action via the magazine and see how it functions.If everything seems good, go shoot the sucker.

If you want, you can send either myself or Hungry 5 fired cases, and we will measure them and tell you what your headspace is.

When I swapped bolts, I went from 1.642", to 1.628". Minimum SAAMI spec for a .308Win. Chamber is 1.630". Now my chamber is at two thou crush, which is exactly what my old TRW M14 was at. Now, if you reload, you will have to readjust your sizing die accordingly. Also, no more shooting cheap surplus ammo.You will now have a nice tight match chamber!!!

After you are all done, MAKE SURE YOU CLEAN OFF ALL TRACES OF THE VALVE LAPPING COMPOUND.


I don't know exactly where you are located in Ontario, but if you are close to Hungry, I'm sure he wouldn't mind giving you a hand. It's a bit of a long drive for me.

It is actually pretty easy to fit the bolt, and it feels good knowing that you did it yourself.
Click to expand...

This pic shows the special bolt lapping toll I used when I built my M14 EBR.
Receiver with the bolt lapping tool installed.
10008570ez.jpg

This tool ensures the bolt lugs are lapped true to the receiver.

This tool takes the place of using a sized case as a guide.

If you are not really handy, or don't have a set of headspace guages, I would STRONGLY recomend taking the rifle to a gunsmith who is familar with M14 type rifles and let him have a look at it.

If you go too far, you have just ruined a $200.00+ USGI bolt.:eek:

SKBY.
 
I'm with Skullboy on this one.

Your chamber right now has about a 2 thou crush. Quite dangerous if you don't know what you are doing. I'm afraid to recommend the lapping process since you will wear away that reciever face(s) and the lugs. Now if you rebarrel with a Douglas or Hart or Obermyer or Mike Rock 5R or Krieger National Match profile barrel, then the lapping to the new barrel is worth the price of the bolt.

Frankly, keep that bolt and use the Norinco bolt for the time being. Once you lap THAT bolt to THAT rifle, you have basically 'committed' that bolt to that rifle.

I don't want to say any more. Leave things be.

Barney
 
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