How Strong Is It?

[DG870]

I have a rifle built on a Kar98 action that is a small ring 98 Mauser action with a large shank barrel. The rifle is chambered in 7x57 and is barreled with a light weight barrel with a contour similar to the Winchester featherweight barrel. I’m loading 139 grain Hornady bullets with 47 grains of H-414 with a muzzle velocity 2750 fps according to Hodgdon data but I haven’t chronographed it. I’ve read conflicting articles on the strength of this action with some saying that because of the thin receiver walls where the barrel is threaded that it should be loaded to pressures like model 93 Mausers and other say that it is a 98 action so load’er up. This load is a maximum for the 7x57 which is 45,000 cup. I think I’m within safe pressure limits with rifle and it shows no pressure signs on the fired brass.

Does any one on the forum have a rifle in this action? If so, what have your experiences been with the strength of the action and what pressure levels do you consider safe. Thanks!

 

[7x57Joe]

Nice rifle. If it is an Erfurt action, it was produced for the 8x57IS cartridge which, according to CIP has an average maximum pressure of 3900 bar or 56564 psi.

 

[DG870]

Thanks for the information. i Bought this several years ago because I’d always wanted a 7x57. I thought I was buying a 98 Mauser in 7x57 but I didn’t realize is was a small ring until I was cleaning it and my 35 Whelen built on a FN Mauser action at the same time and noticed the difference in the actions (I know, what a dummy). I have a couple Swedish Mauser 96s that are small rings but didn’t realize they made small ring 98s. Ive read that as long as you keep it chambered is something like a 7x57 and keep your loads orighnal pressures, 45.000 cup, that it would be ok. It is a nice rifle and over 100 years old so I don’t want to abuse it. I’ve been shooting it more lately and plan to use it deer season this year. Guess I’m still learning things.

 

[7x57Joe]

The old 7x57 has proved itself for over 120 years. It's deadly with a 175 grain bullet traveling at 2400 fps as well as a 140 at 2600 fps. One can speed these up slightly if there's a perceived need but, it works fine at these velocities.

 

[Joker12]

I have an early Browning Safari grade rifle factory chambered for 308 built on a F.N. small ring action. The 308 operates at much higher pressure than a 7x57. Considering that it makes sense that your 7x57 is a perfectly safe rifle at modern pressure levels for the 7x57.

 

[gibbs30c]

First you have a very fine rifle built on a very fine light weight action, a Small Ring (SR) '98 Action. I have several most in the 1910 and 1934 "Mexican Mauser" form.

Nothing will get so called gun/action experts going more than the strength of the SR versus the LR Mauser actions. Most just repeat what they have heard and read on forums like this one. And most will always compare any SR to the '93 SR which in itself can be found in many varying manufacturing conditions of quality. Most when referring to the '93 are talking about the Spanish '93 many which the Spanish Gov. converted to 7.62 Nato (308 win) and this has many of these experts driven to extreme reaction. Some even claim the Spanish Military only intended them to be used with a reduced power load. While such a load may have existed..... the Spanish fully intended for them to also be used with full power Nato rounds from other countries if a conflict should ever occur.

The SR Mauser line does not begin with the '93 but rather the '91 some would even say the '88. it included the '94's, '95's, and '96's. And later the SR '98's

The '94's through the '96's are of much better quality than most of the '93's. But even the '93's can handle pressures up to 45K. I have heard........ but don't know for certain that the Spanish conversions have been proofed to 60K. That may or may NOT be true.

Your action is modified and redesigned to carry the '98 bolt in that different SR design, as does the Mexican 1910 and 1934 and many other commercial and military models. It is best described as a hybrid between the SR '91 thru '96 and the LR '98.

Many people think the '98 is far superior because they believe it has "Three" locking lugs. It does not!
It has only two forward lugs that lock in battery.

The so called third rear lug is a safety lug and does not bear during battery or under load during firing. Many of the later SR Mauser designs used the Bolt handle as a safety lug.

The '98's are found in many different ring and thread sizes both SR and LR barrel shanks and both SR and LR ring sizes with the different shank sizes. This is true for both military and commercial models.

But for sure ALL '98's both SR and LR are stronger than the SR's '91 thru '96.

Are all '98's equally as strong? NO, it all depends on steel used heat treatment etc. But most of the old time experts used to say the Mauser achieves it's strength from it DESIGN and not special steels or heat treat.

Again that is true to only some extent. P.O.Ackely did extensive research and testing on the strength of various military actions and his book can be found on Kindle books. I strongly recommend it for people wanting to learn about action strength, and "blow-ups" He basically found it takes a LOT to destroy an action.

The Mexicans converted many of their 1934's and I believe the 1910's to fire the 30/06. They did this by lengthening the action by trimming the bottom feed ramp. This of course also weakened to some degree the bottom lug. This also has some declaring these rifles unsafe.

But to be sure both the Mexicans or the Spanish fired millions of rounds through these converted rifles with no ill effects that I have ever heard of.

The claim that the lesser metal of the SR '98 around the barrel shank weakens the action, has never made sense to me. Simply because the pressure of the round is contained in the rifles chamber and not by the action ring.

It is true that the less metal of the ring lessens the holding power of the locking lugs but if a barrel chamber were ever to split you have a lot more problems than the locking lugs!!!!!!!

These people also declare the Springfield 1903 both A1 and A3 a very strong action not realizing it is itself a SR action. The ring dia. of the Springfield is 1.305, the SR Mauser is 1.30, and the LR Mauser is 1.41. So you can see the Springfield which many convert to Mag. rounds is closer to your SR Mauser '98 than the LR Mauser.

For sure ANY action can be destroyed or blown up by extremely overloaded handloads or by a bore obstructions. But your load is no where near that extreme.

Nothing is more joyful than climbing up to the tundra with a fine light weight SR Mauser on your shoulder in a fine flat shooting hard hitting caliber.

YOU HAVE such a rifle, enjoy it.........it DOES NOT want to kill you!

 

[SaintPanzer]

Just curious, are there any proof marks? If so, it's been fired at least once at 125% max load...

 

[Ontario Hunter]

First you have a very fine rifle built on a very fine light weight action, a Small Ring (SR) '98 Action. I have several most in the 1910 and 1934 "Mexican Mauser" form.

Nothing will get so called gun/action experts going more than the strength of the SR versus the LR Mauser actions. Most just repeat what they have heard and read on forums like this one. And most will always compare any SR to the '93 SR which in itself can be found in many varying manufacturing conditions of quality. Most when referring to the '93 are talking about the Spanish '93 many which the Spanish Gov. converted to 7.62 Nato (308 win) and this has many of these experts driven to extreme reaction. Some even claim the Spanish Military only intended them to be used with a reduced power load. While such a load may have existed..... the Spanish fully intended for them to also be used with full power Nato rounds from other countries if a conflict should ever occur.

The SR Mauser line does not begin with the '93 but rather the '91 some would even say the '88. it included the '94's, '95's, and '96's. And later the SR '98's

The '94's through the '96's are of much better quality than most of the '93's. But even the '93's can handle pressures up to 45K. I have heard........ but don't know for certain that the Spanish conversions have been proofed to 60K. That may or may NOT be true.

Your action is modified and redesigned to carry the '98 bolt in that different SR design, as does the Mexican 1910 and 1934 and many other commercial and military models. It is best described as a hybrid between the SR '91 thru '96 and the LR '98.

Many people think the '98 is far superior because they believe it has "Three" locking lugs. It does not!
It has only two forward lugs that lock in battery.

The so called third rear lug is a safety lug and does not bear during battery or under load during firing. Many of the later SR Mauser designs used the Bolt handle as a safety lug.

The '98's are found in many different ring and thread sizes both SR and LR barrel shanks and both SR and LR ring sizes with the different shank sizes. This is true for both military and commercial models.

But for sure ALL '98's both SR and LR are stronger than the SR's '91 thru '96.

Are all '98's equally as strong? NO, it all depends on steel used heat treatment etc. But most of the old time experts used to say the Mauser achieves it's strength from it DESIGN and not special steels or heat treat.

Again that is true to only some extent. P.O.Ackely did extensive research and testing on the strength of various military actions and his book can be found on Kindle books. I strongly recommend it for people wanting to learn about action strength, and "blow-ups" He basically found it takes a LOT to destroy an action.

The Mexicans converted many of their 1934's and I believe the 1910's to fire the 30/06. They did this by lengthening the action by trimming the bottom feed ramp. This of course also weakened to some degree the bottom lug. This also has some declaring these rifles unsafe.

But to be sure both the Mexicans or the Spanish fired millions of rounds through these converted rifles with no ill effects that I have ever heard of.

The claim that the lesser metal of the SR '98 around the barrel shank weakens the action, has never made sense to me. Simply because the pressure of the round is contained in the rifles chamber and not by the action ring.

It is true that the less metal of the ring lessens the holding power of the locking lugs but if a barrel chamber were ever to split you have a lot more problems than the locking lugs!!!!!!!

These people also declare the Springfield 1903 both A1 and A3 a very strong action not realizing it is itself a SR action. The ring dia. of the Springfield is 1.305, the SR Mauser is 1.30, and the LR Mauser is 1.41. So you can see the Springfield which many convert to Mag. rounds is closer to your SR Mauser '98 than the LR Mauser.

For sure ANY action can be destroyed or blown up by extremely overloaded handloads or by a bore obstructions. But your load is no where near that extreme.

Nothing is more joyful than climbing up to the tundra with a fine light weight SR Mauser on your shoulder in a fine flat shooting hard hitting caliber.

YOU HAVE such a rifle, enjoy it.........it DOES NOT want to kill you!

Thanks. Very informative! I had no idea my Springfield 03A3 was just a puny small ring. I seem to recall one converted to 458 Win up for sale on here not too long ago. My best friend in Montana has one built up to 7mm Rem Mag and it seems to handle those pressures just fine.

 

[DG870]

Thanks for all the information. I have attached a couple of pictures. The rifle has been rebarreled with a lightweight 24 inch barrel. There are no markings on the barrel other than the cartridge. The receiver ring has some stamps but I’m not sure if they’re proof marks.

 

[Wyatt Smith]

The Spanish did have a reduced power load. The 7.62 CETME. It was intended for for use in the CETME rifle, the predecessor or the HK G3/91.
Wether or not it was also meant to be used in the Mausers or what came first I have no idea.

 

[gibbs30c]

I would not call the Springfield punny but it for sure was designed after the '93 Mauser after the Spanish American War taught the American the value of the Mauser.

A Springfield is just a modified Mauser, but much stronger than the '91 thru '96 Mausers.

You are correct MANY Springfields have been converted to 458 win mags and just about every other Standard Length belted mag you can name.

They handle those conversions with ease. The only real problem with the Springfield is the Rock Island manf. in serial numbers some say 200,000 and below, some say 275,000 and below, and some say 600,000 and below as they were recalled and reheat treated to a very hard and brittle state.

Those Rock Island rifles have had some real failures, but because of the reheat treat and NOT the design.

The Springfield is in a class with the LR '98 Mauser and is a step above your '98 SR and three steps above the '96 and below SR Mausers.

The Stamp marks on your actions are indeed proof marks, and SaintPanzer is correct it has been proofed to 125%. From the pics your action is in excellent shape with no pitting and it will handle any 7X57 load any SANE man would feed it. As always start your loads low and work up slowly watching for pressure signs. No deer or elk on earth ever knew the difference from a round moving 100 FPS faster or one 100 FPS slower, when hit.

Enjoy your SR '98 it is a fine rifle......and good hunting.

 

[SaintPanzer]

Those look like proof marks on the receiver. I had thought they were London and Birmingham proofs, but they don't quite look right, and I don't recognize them. They do not look like German proof marks either, I would expect to see the Ulm proof house antler. There may be more info covered by the stock. The barrel should have similar, but you've said it's been re-barreled, so it was probably not re-proofed after the new barrel.