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What Should I Know Are Warning Signs If They Appear Testing .300 Win Mag Turk


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Kenak,

 

Whats kunhausen's procedure for this, I don't have his book.

 

Thanks,

 

Roy

 

Items in () are my addlibs

Standard pressure Proofing:

From Jerry Kuhnhausen's The Mauser Bolt Actions M91 through M98

Page 195

 

1. Detail clean and completely dry the chamber, bore, and action.

 

 

2. Install barreled action in test firing fixture secured to test stand. (Lash to solid bench or spare tire)

 

3. Select factory ammunition in the mid weight bullet range. (150 grain for .300 win)

 

4. Roll cartridge on a case lube pad moistened with gun oil until the main case is lightly an evenly oil coated. Make sure that the case neck, shoulder, cartridge head, primer, and bullet are not oiled, and are 100% dry.

 

5. Put on suitable ear protection, place a round, oil coated as above, in the chamber, and lock the bolt. Stand clear, and fire the barreled action with a lanyard.

 

6. Open the bolt and check case extraction. Lightly lubricated cartridge cases should not be hard to extract from a well reamed, polished and correctly headspaced chamber. If case extraction is stiff, check headspace. If headspace is OK, go to step 7.

 

7. Now, test fire four more rounds under the same conditions and closely inspect brass for possible chamber or primer problems.

 

8.Detail clean the chamber, bore, and bolt face, after proof firing, and regage headspace. If headspace is OK and the receiver and the bolt lugs appear as lapped and reheat treated earlier, (assuming you lapped the lugs and had the receiver reheat treated) the barreled action can be considered serviceable.

 

If headspace has increased .001” or more, the receiver lugs area and/or bolt lugs may be soft. Remove barrel and inspect receiver for possible lug area seating or setback. Also inspect bolt lugs for seating. Reject the defective parts(s) and mark them not safe to fire.

 

 

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  • 1 month later...

I went out to the range out at french creek this morning trying to get there before anyone else to test it, But a ranger who was in the parking area walked over and said I could'nt fire it with a string on the range, I probably should have put the stock on it but if something does go wrong I don't want to destroy it, I already gave away the turk stock. I guess I'll have to wait until next month when I go up to my cabin to test it on my own land.

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Guest Uncle carbuncle

Look all, I'm normally big on the whole headspace issue but in this case it is the last thing I'd be concerned about. The real issue as I see it is "how much material is surrounding the chamber walls?"

 

I can't confirm or refute the previous poster's comments on the Weatherby. If it is true, then one could likely conclude that then too must the Turk SR magnum conversion be. I however suscribe to the notion that there are better actions available for very little increase in cost. Like the vz24 that the poster alluded to.

 

Hatcher noted that in experiments he did with the '03 springfield, the chamber walls were reduced to only .150" and they held with NORMAL sevice loads. However, things went south very quickly when pressures started to increase. The calculations I did place the Turk Magnum conversion chamber walls just slightly over that minimum. Which I suppose should suffice if you never had a pressure spike. Big IF in my book. Frankly I don't have the time or energy to either prove or disprove the safety issue, thus I will simply avoid it by not using the SR thread 98's for magnum conversions. I ahve boxes of both actions. The SR Turks will be built into -06 casehead derived chamberings and the others would be used for any Magnum cartridges I might decide to build.

 

 

This is sound advice. Your oiled cartridges test is not likely to verify that there is sufficent metal around the chamber area.

 

Post some pics of your conversion.

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Uncle cautious, uncle carbuncle

 

I am greatful for your concern, This is why I ask questions here there is a lot of experience with our members, I need to test this one , I will do it safely and check for any bulges in the barrel and use all of the info above (oiled cartridges checking inside of case and removing barrel and looking for setback) .

 

 

Thanks,

 

Roy

 

 

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  • 4 weeks later...

well bubba, with a barreled action strung up in a tree with duct tape, i'm afraid to say you have earned your screen name! :)

 

glad the action's holding....

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well bubba, with a barreled action strung up in a tree with duct tape, i'm afraid to say you have earned your screen name!

 

Don't laugh - the last four rifles I test fired were tied to the side of tree pointing down into the creek behind the house; crude but effect. One of these days I'll get around to building a test firing jig...

 

Bubba, do be careful please.

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Guest Guest

If a Ruger M77 requires a barrel shank .998 in diameter and

Small ring Mauser requires .980 is this .018 difference going

to make the rifle unsafe?

 

The belt on a 300 H&H "parent case to a family of magnums" is .532

in diameter. The 30/06 case diameter is .473

 

In a standard 30/06 chambering the chamber wall thickness would be

 

For the Ruger (.998-.473)/2= .2625

For the Small ring (.980-.473)/2= .2535

difference .009

 

 

So for the Magnum the chamber thickness would be

For the Ruger (.998-.532)/2=.233

For the Small ring (980-.532)/2=.224

difference .009

 

Now the difference in the thickness of the chamber wall between

a standard and a magnum is .0295

(.532-.473)/2=.0295

 

 

Standard thickness-Magnum thickness)

 

Ruger M77 .2625-.233=.0295

 

Small ring .2535-.224= .0295

 

difference between magnum chamber wall thickness

of a M77 and Small Ring

.2625-.2535= .009

 

So is .009 and unsafe margin?

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Guest,

 

Your calcs are way off. You must consider two additional factors. First the thread count. Coarser threads are deeper. Thus the mauser threads leave less material around the chamber than the Ruger's finer threads do. Second, relief cuts? Are there any on the barrel shank? How deep is it? Often, the relief just behind the shoulder is deeper than needed.

 

Try calculating based off of the minimum diameter, the diameter as measured at the bottom of the "V" in the threads not the crest of the threads. There is considerable difference. Once you do that you will be surprised at how little metal really is left over that magnum chamber.

 

The last time we ran these numbers the SR magnum mauser chamber walls calculated out to somwhere around .180".

 

As I said before, setback would be the least of my concerns.

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I think that these numbers are correct. I used the diameter immediately in front of the belt (<-- arrow is barrel wall thickness).

 

Turk Large Ring/Small Shank Mauser

--------

Cartridge just forward of the belt: 0.5130

 

Barrel shank thread (major) diameter: 0.980

 

Receiver diameter: 1.410

 

Thread type: 12V

 

Minor Diameter:

0.980 - (2 X (cos 30 deg)/TPI) = 0.980 - (2 X 0.866/12) = 0.8357

 

Effective Barrel Wall thickness:

((Minor Diameter) - (Case Diameter))/2 = (0.8357 - 0.513)/2 = 0.1613 <--

 

Total wall thickness case:

((rec. dia.) - (case dia.))/2 = (1.410 - 0.5130)/2 = 0.449

 

 

Ruger M-77

--------

Cartridge just forward of the belt: 0.5130

 

Barrel shank thread (major) diameter: 0.998

 

Receiver diameter: 1.315

 

Thread type: 16V

 

Minor Diameter:

0.998 - (2 X (cos 30 deg)/TPI) = 0.998 - (2 X 0.866/16) = 0.8898

 

Effective Barrel Wall thickness:

((Minor Diameter) - (Case Diameter))/2 = (0.8898 - 0.513)/2 = 0.1884 <--

 

Total wall thickness case:

((rec. dia.) - (case dia.))/2 = (1.315 - 0.5130)/2 = 0.401

 

 

Remmington M-700

--------

Cartridge just forward of the belt: 0.5130

 

Barrel shank thread (major) diameter: 1.050

 

Receiver diameter: 1.360

 

Thread type: 16V

 

Minor Diameter:

0.998 - (2 X (cos 30 deg)/TPI) = 1.050 - (2 X 0.866/16) = 0.94175

 

Effective Barrel Wall thickness:

((Minor Diameter) - (Case Diameter))/2 = (0.9415 - 0.513)/2 = 0.2144 <--

 

Total wall thickness:

((rec. dia.) - (case dia.))/2 = (1.360 - 0.5130)/2 = 0.4235

 

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Guest Guest

Factoring in the receiver walls is misleading. You assume 100% contact which doesn't exist.

 

You must

I think that these numbers are correct. I used the diameter immediately in front of the belt (<-- arrow is barrel wall thickness).

 

Turk Large Ring/Small Shank Mauser

--------

Cartridge just forward of the belt: 0.5130

 

Barrel shank thread (major) diameter: 0.980

 

Receiver diameter: 1.410

 

Thread type: 12V

 

Minor Diameter:

0.980 - (2 X (cos 30 deg)/TPI) = 0.980 - (2 X 0.866/12) = 0.8357

 

Effective Barrel Wall thickness:

((Minor Diameter) - (Case Diameter))/2 = (0.8357 - 0.513)/2 = 0.1613 <--

 

Total wall thickness case:

((rec. dia.) - (case dia.))/2 = (1.410 - 0.5130)/2 = 0.449

Ruger M-77

--------

Cartridge just forward of the belt: 0.5130

 

Barrel shank thread (major) diameter: 0.998

 

Receiver diameter: 1.315

 

Thread type: 16V

 

Minor Diameter:

0.998 - (2 X (cos 30 deg)/TPI) = 0.998 - (2 X 0.866/16) = 0.8898

 

Effective Barrel Wall thickness:

((Minor Diameter) - (Case Diameter))/2 = (0.8898 - 0.513)/2 = 0.1884 <--

 

Total wall thickness case:

((rec. dia.) - (case dia.))/2 = (1.315 - 0.5130)/2 = 0.401

Remmington M-700

--------

Cartridge just forward of the belt: 0.5130

 

Barrel shank thread (major) diameter: 1.050

 

Receiver diameter: 1.360

 

Thread type: 16V

 

Minor Diameter:

0.998 - (2 X (cos 30 deg)/TPI) = 1.050 - (2 X 0.866/16) = 0.94175

 

Effective Barrel Wall thickness:

((Minor Diameter) - (Case Diameter))/2 = (0.9415 - 0.513)/2 = 0.2144 <--

 

Total wall thickness:

((rec. dia.) - (case dia.))/2 = (1.360 - 0.5130)/2 = 0.4235

 

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Guest Guest

My father put an old shotgun in a tree and pulled a trigger string before I was born in 1951.

 

Then he designed the M110 with an equilibrator and then the army gave his a single bid contract to design the M107 that fought in Viet Nam. He had an equilibrator design that balanced the 20 ton barrel so it could be controlled with a 5 inch pound torque oil pump, despite barrel attitude or slope of the land. The generals thought that they would remote control large batterys of guns, but it didn't work out that way.

 

IPB Image

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  • 5 months later...

I have'nt seen any signs of problems through 2 boxes of ammo fired with the oil test listed above one box 150 one 200 gr., I have a chunk of wood I've started to copy a macmillian stock style into for it (if I ever get around to it). The first rifle i did was a little over a year ago now i have 3 going at once (or rather various degrees of finished .this one, cetme, mosin sporter)

 

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