9.3x62 in small ring, large shank Kar.98?

Jason

"You're not hard-core, unless you live hard-core."
_______________________

Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt.

Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry
Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure.

-Jason Brown

01 September 2010, 23:38

ramrod340

I wouldn't think of that project on that action.

02 September 2010, 00:02

ForrestB

Start with a worthy action. It's the lowest cost component of the rilfe you're building.

02 September 2010, 00:06

nsaqam

The 9.3x62 operates at the same pressure as the 7x57 and the 8x57.
The 9.3x62 has magnum killing power combined with modest pressure.
The 9.3x62 is no fatter than the others either so you have the same amount of steel around the chamber.
I would be concerned about any cuts into the receiver ring since these would reduce the strength.
Eliminate the square bridge cuts and I wouldn't hesitate making a nice sleek rifle out of that action.

02 September 2010, 01:06

Fal Grunt

quote:
Originally posted by nsaqam:
Eliminate the square bridge cuts and I wouldn't hesitate making a nice sleek rifle out of that action.

Let me show my ignorance to the above comments. Why is a Kar. 98 action so inferior? I have plenty of mauser actions, everything from Yugo, czech, to military Oberndorf and DWM, but I do not see how this Danzig 1912 Kar. 98 action is inferior? Is it merely because it is a small ring? It is actually a super nice action (in my opinion) nice tight but smooth bolt fit, machining is very well done, no pitting anywhere...

nsaqam, this is precisely why the customer wants to use this action. Slim, sleek, lightweight. I am confused by your comment about the square bridge cuts? The square bridges will be mounted onto the ring, then the cuts for the Talley rings will be into those "bridges". No cuts into the ring will be made. The only cuts will be along the left and right side, below the wood line.

Ok gents, I appreciate your opinions, but I need more of your reasoning! I will be the first to admit I have a LOT to learn... please expound apon the basis or reasoning of your opinions.

thanks so much!

02 September 2010, 01:27

Bobster

The receiver ring on the Kar98 is thinner than any other model including the M93 small rings. Even though it operates at the same chamber pressure as the 7x57, the heavier bullets exert more back force on the locking lugs. The Germans quit making it for a reason.

Below is a pic of a M93 that grenaded from a case head separation firing .308Win. Notice how thin the steel is at the top of the receiver ring. Since your receiver has a large ring barrel in it, it is thinner than that! I just wouldn't want to risk it.

02 September 2010, 01:43

nsaqam

quote:
Originally posted by Fal Grunt:
quote:
Originally posted by nsaqam:
Eliminate the square bridge cuts and I wouldn't hesitate making a nice sleek rifle out of that action.

Let me show my ignorance to the above comments. Why is a Kar. 98 action so inferior? I have plenty of mauser actions, everything from Yugo, czech, to military Oberndorf and DWM, but I do not see how this Danzig 1912 Kar. 98 action is inferior? Is it merely because it is a small ring? It is actually a super nice action (in my opinion) nice tight but smooth bolt fit, machining is very well done, no pitting anywhere...

nsaqam, this is precisely why the customer wants to use this action. Slim, sleek, lightweight. I am confused by your comment about the square bridge cuts? The square bridges will be mounted onto the ring, then the cuts for the Talley rings will be into those "bridges". No cuts into the ring will be made. The only cuts will be along the left and right side, below the wood line.

Ok gents, I appreciate your opinions, but I need more of your reasoning! I will be the first to admit I have a LOT to learn... please expound apon the basis or reasoning of your opinions.

thanks so much!

I understand now.
I thought there was going to be cuts made into the ring itself.

02 September 2010, 07:42

ramrod340

I have a safety issue with the large shank small ring. Yes I know many say they are safe "IF" you keep the pressure low. Yes a 9.62x62 was a lower pressure than say a 308 or 30-06. You are ASSUMING that all future reloads and owners will operate at a low pressure. To me a small ring small shank gives more meat and makes me feel better pulling the trigger.

If I was going to build a custom rifle and do all that you mentioned I would not start with a lower grade action. As Forrest stated the action cost is a very small % of the total cost. Start with a higher quality action the overall cost of the project will not increase much and the value and future resale will be MUCH higher.

02 September 2010, 20:57

DKim

Small ring - small shank vs. Small ring - large shank: Isn't the amount of metal around the cartridge the same (assuming receiver ring diameters are equal)? They differ in how the metal is distributed between the receiver and barrel. I do not dispute the evidence that it makes a difference.

David

02 September 2010, 23:09

J.D.Steele

The barrel's thread shank isn't the weak point here. The receiver ring's hoop strength is necessarily reduced but the usual failure mode for this combination is the increasing headspace caused by the actual longitudinal stretching of the thin receiver ring wall, especially on the right side in the extractor relief. The receiver ring wall in this combination is thinner than in any other Mauser design and is a known weak point that isn't present with the SR/ST or LR/LT designs.
Regards, Joe

03 September 2010, 00:29

theback40

This may be a stupid question, but here goes...
Would tougher, meaning higher rockwell steel barrel give you anymore room for error in a small ring, large thread? I remember seeing in Rifle mag a testing of differant barrel man. and the Rc of each, they ranged from R10 to 28-30

03 September 2010, 01:20

J.D.Steele

quote:
Originally posted by J.D.Steele:
The barrel's thread shank isn't the weak point here.Regards, Joe

03 September 2010, 01:49

airgun1

I am in total agreement with J.D. I like Kar98a actions and have built lots of 257 Roberts and 30-06 on them through the years. They are not a blow up threat like a low numbered Springfield any more or less than any other action. The increase in headspace over time will occur. They are paper thin in the area of the receiver between the barrel threads and lucking lugs.

Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

quote:
Originally posted by J.D.Steele:
The barrel's thread shank isn't the weak point here. The receiver ring's hoop strength is necessarily reduced but the usual failure mode for this combination is the increasing headspace caused by the actual longitudinal stretching of the thin receiver ring wall, especially on the right side in the extractor relief. The receiver ring wall in this combination is thinner than in any other Mauser design and is a known weak point that isn't present with the SR/ST or LR/LT designs.
Regards, Joe

03 September 2010, 01:58

gzig5

quote:
Originally posted by Bobster:
The receiver ring on the Kar98 is thinner than any other model including the M93 small rings. Even though it operates at the same chamber pressure as the 7x57, the heavier bullets exert more back force on the locking lugs. The Germans quit making it for a reason.

The second half of that statement doesn't quite agree with physics. Thrust on the lugs is equal to the chamber pressure times the area of the case head, actually the internal area at the base if I remember correctly. The larger the base diameter, the more force is applied to the lugs. Bullet weight will effect recoil energy, but that is a different animal.

03 September 2010, 02:50

nsaqam

quote:
Originally posted by airgun1:

Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

That is an astoundingly good suggestion which I hadn't considered before.
I happen to have a nice LR/SS Turk action that is asking to be my boys first BG rifle with both of us working on it over the next several years.

03 September 2010, 03:56

airgun1

Here is a turk surface ground by Gary Stiles to smallring dimensions.

03 September 2010, 05:51

Fal Grunt

Well thanks for the input everyone

Hopefully it was educational for more than just me!

One thing to be aware of with the turks, the thread pitch and size vary due to the variety or origin.

Airgun1 that looks great. I was thinking about making a fixture to grind rings, might have to get on that sooner than later.

03 September 2010, 06:18

nsaqam

quote:
Originally posted by airgun1:
Here is a turk surface ground by Gary Stiles to smallring dimensions.

That really looks great airgun!
I wonder if I could do that with my tool post grinder?
Looks like I have some experimenting to do on the lathe.

03 September 2010, 08:03

gzig5

quote:
Originally posted by airgun1:
Here is a turk surface ground by Gary Stiles to smallring dimensions.

I don't see how you can bring yourself to take that to the range considering it's poor man's lineage.

03 September 2010, 08:17

z1r

quote:
Originally posted by airgun1:
Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

Depending on the Turk action you start with the end product could be just as undesirable as using a SR Large Thread 98.

03 September 2010, 08:35

nsaqam

quote:
Originally posted by z1r:
quote:
Originally posted by airgun1:
Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

Depending on the Turk action you start with the end product could be just as undesirable as using a SR Large Thread 98.

No matter what you'll have a thicker, stronger receiver ring with the SS Turk than you would with the SR/LS action.

03 September 2010, 09:11

Redoak8

The 1903 Turks are almost identical to the esteemed LR SS intermediate length 1909 Peruvians. And although lots of them look rough externally, many are still very slick and smooth to operate, and after surface grinding, make excellent actions.

But I think they might be a bit short for the 9.3x62....

03 September 2010, 09:18

z1r

quote:
Originally posted by nsaqam:
quote:
Originally posted by z1r:
quote:
Originally posted by airgun1:
Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

Depending on the Turk action you start with the end product could be just as undesirable as using a SR Large Thread 98.

No matter what you'll have a thicker, stronger receiver ring with the SS Turk than you would with the SR/LS action.

Not necessarily true, depends on which receiver you start with.

03 September 2010, 09:21

z1r

quote:

But I think they might be a bit short for the 9.3x62....

Here's a 1909 Peruvian with a 9,3x62 round:

Pic courtesy of Jack Belk.

The 1903 turk was altered for the 8x57 round. the mag box is typically 3.320" whilst the 9,3x62 has a Max OAL of 3.290".

03 September 2010, 09:39

nsaqam

quote:
Originally posted by z1r:
quote:
Originally posted by nsaqam:
quote:
Originally posted by z1r:
quote:
Originally posted by airgun1:
Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

Depending on the Turk action you start with the end product could be just as undesirable as using a SR Large Thread 98.

No matter what you'll have a thicker, stronger receiver ring with the SS Turk than you would with the SR/LS action.

Not necessarily true, depends on which receiver you start with.

As long as the Turk is threaded for the SS (small shank) barrel the ring will be thicker than the ring on the SR/LS Mauser.

03 September 2010, 09:42

z1r

quote:
Originally posted by nsaqam:
quote:
Originally posted by z1r:
quote:
Originally posted by nsaqam:
quote:
Originally posted by z1r:
quote:
Originally posted by airgun1:
Buy a turk action with large ring small thread and turn it into a 33/40 lightweight.

Depending on the Turk action you start with the end product could be just as undesirable as using a SR Large Thread 98.

No matter what you'll have a thicker, stronger receiver ring with the SS Turk than you would with the SR/LS action.

Not necessarily true, depends on which receiver you start with.

As long as the Turk is threaded for the SS (small shank) barrel the ring will be thicker than the ring on the SR/LS Mauser.

Not in all places.

03 September 2010, 10:27

jeffeosso

quote:
Originally posted by Bobster:
Even though it operates at the same chamber pressure as the 7x57, the heavier bullets exert more back force on the locking lugs.

no, sir, and with respect, this is disinformation.

psi*surface area is bolt thrust.. doesn't matter if its a 257 weatherby or 458lott, it is EXACTLY the same...

its math, not subject to opinion

03 September 2010, 16:58

airgun1

It is not mine to hunt with. It was my son's graduation gift from me and all of my gunsmith buddies in 2005. There are more pics in an older thread under custom rifles here.

The turk action I am referring to is what we commonly and erroneously call the 1938, M38, etc turk. They are rough but strong; they clean up nicely.

04 September 2010, 01:47

F. Guffey

The 03 Springfield receiver OD is 1.350, the ORIGINAL Mauser OD is 1.350, the barrel on the Original Mauser has an OD shank of .980, the shank on the 03 OD is 1.040, that makes the Springfield marginal with a receiver ring .060 thousands thinner than the original Mauser.

http://www.turkmauser.com/models.aspx

I will go with the Doc. and Big 5 Sports, the label on the end of the box reads model 38, the Doc. says that is a configuration, I have 38s that are configured from large ring/large shank CZ 22 (some stamped 23) rifles, thinking I was getting a large ring/small shank type rifle? Complaining did not occur to me.

F. Guffey

04 September 2010, 04:45

Bobster

quote:
Originally posted by jeffeosso:
quote:
Originally posted by Bobster:
Even though it operates at the same chamber pressure as the 7x57, the heavier bullets exert more back force on the locking lugs.

no, sir, and with respect, this is disinformation.

psi*surface area is bolt thrust.. doesn't matter if its a 257 weatherby or 458lott, it is EXACTLY the same...

its math, not subject to opinion

So Jeff, are you saying the +1,000 ft lbs of energy difference between a 7x57 and 9.3x62 is not transmitted to the locking lugs? Remember, the bullet base has surface area and the bullet has mass. Newton's Third Law - For every action there is an equal and opposite reaction. How is that extra force transmitted to my shoulder if not through the locking lugs or am I just imagining it? You are correct if talking about the same weight bullets at the same pressure in the same head size case. But 9.3 bullets are much heavier than 7mm and therefore must exert more back force in proportion when acted on by the same chamber pressure-according to Newton.

04 September 2010, 05:04

airgun1

The turks would take any mauser and modify it to outwardly appear like their primary weapon. Your's sounds like a WWI Gew 98 that they turned (recessed) part of the receiver ring to retain the handguard like the other turks in service at the time. There is only 3 thread holdiong that barrel on.

Also large ring mauser threads are 1.10" and the inner portion of the receiver rings are vastly different between Kar98a and M1903 Springfields. Comparing apples and oranges. The Kar98a will work but it will not work nearly as long a large ring 98, i.e. Gew 98, 98k, VZ-24 etc.

quote:
Originally posted by F. Guffey:
The 03 Springfield receiver OD is 1.350, the ORIGINAL Mauser OD is 1.350, the barrel on the Original Mauser has an OD shank of .980, the shank on the 03 OD is 1.040, that makes the Springfield marginal with a receiver ring .060 thousands thinner than the original Mauser.

http://www.turkmauser.com/models.aspx

I will go with the Doc. and Big 5 Sports, the label on the end of the box reads model 38, the Doc. says that is a configuration, I have 38s that are configured from large ring/large shank CZ 22 (some stamped 23) rifles, thinking I was getting a large ring/small shank type rifle? Complaining did not occur to me.

F. Guffey

04 September 2010, 07:10

dpcd

You are correct in your assertion that there is no correlation between either muzzle energy or recoil energy, and chamber pressure. It is not necessarily intuitive, but true.

04 September 2010, 07:48

F. Guffey

quote:
There is only 3 thread holdiong that barrel on

airgun 1, "There is only 3 thread holdiong that barrel on" I am not in the habit of making this stuff, to help others I furnished a link, had you read further down the link you would have found mention of the ATF 54, I also have that one and there is nothing suspect about that rifle.

I do not know what "sounds like" is but when I read the stampings on the Brno 22 it 'LOOKS LIKE A BRNO 22, one is stamped 23

And there is no such a think as a TURK with a bad barrel, I have 10 extra with 6 6.5mm55 Swiss barrels. I made no mention of the KAR sr/ls, I made it a point to say original as in small ring/small shank, I did say the 03 was a marginal rifle, Rock Island and Springfield produced 1,000,000 rifles identified as low number, and I make no excuses on their behalf.

F. Guffey

04 September 2010, 23:24

airgun1

My post is a bit ambiguous as were both of yours. That is a good link.

I meant yours was similar not that you had a Gew 98 and mistakenly called it a 22 or 23. I know that when it comes to turk mausers, you find somekind of variations; as I said they made them look cosmetically the same depending on the era.

You said the dimension that ended up being .060" smaller; my post was merely reinforciong that the Kar98a was worse yet because the threads are even larger, that is all. I was not being critical of your posts in the least. We know what we want to say but it sometimes doesn't make it to our fingers.

05 September 2010, 00:26

jeffeosso

quote:
Originally posted by Bobster:
quote:
Originally posted by jeffeosso:
quote:
Originally posted by Bobster:
Even though it operates at the same chamber pressure as the 7x57, the heavier bullets exert more back force on the locking lugs.

no, sir, and with respect, this is disinformation.

psi*surface area is bolt thrust.. doesn't matter if its a 257 weatherby or 458lott, it is EXACTLY the same...

its math, not subject to opinion

So Jeff, are you saying the +1,000 ft lbs of energy difference between a 7x57 and 9.3x62 is not transmitted to the locking lugs? Remember, the bullet base has surface area and the bullet has mass. Newton's Third Law - For every action there is an equal and opposite reaction. How is that extra force transmitted to my shoulder if not through the locking lugs or am I just imagining it? You are correct if talking about the same weight bullets at the same pressure in the same head size case. But 9.3 bullets are much heavier than 7mm and therefore must exert more back force in proportion when acted on by the same chamber pressure-according to Newton.

Bob,
3rd law applies .. however, it doesn't CARE about bullet weight for pressure .. and bolt thrust is pis*surpface area ...

let's back into this...

if you took a X round, and loaded it to 65kpsi, the max pressure would be 65kpsi ... if you loaded a 90gr bullet or a 250gr bullet, the POWDER volume changes, changing the pressure.. you obivoulsy WOULD NEVER take the same 65kpsi charge for a 90gr bullet and try to stuff a 250gr bullet on that.. your pressure would skyrocket, and probably blow up the gun, as you would be likely over 150kPSI, at the same length ...

case in this example is a 300 weatherby ...

and its bolt thrust doesn't change due to bullet weight, it changes to pressure*surface area ... this is why a 223 could be loaded into the TC contender, but a 308win couldn't be ...

But,
don't believe me .. here's a quote from riflebarrels.com

quote:
Bolt Thrust
Bolt thrust is easy to calculate. Only two inputs are required. They are peak chamber pressure in PSI and as mentioned, the inside area of the case head that the gas pressure can work on. The formula then is:

THRUST=AREA*CPSI Where:

AREA=3.1416*(HS/2)^2

HS=the diameter of the inside of the case head.

feel free to read up on it
http://www.riflebarrels.com/ar...olt_lug_strength.htm

since a 90gr bullet could take X grains to make 65kpsi, at a given oal, then a 250gr at the same oal, would take LESS THAN X, to be 65kpsi ...

in this case, the bullet weight changes the working pressure ... but not the bolt thrust.

i can PM you my cell phone number, if you like .. its a tad easier to understand via a voice call ...

but, in a nutshell .. bullet weight accepts pressure .. however, the rounds are loaded to a pressure SPEC ... that pressure*surface area is bolt thrust ...