Mauser case hardness ?

[robroy]

I've got a couple of FN 98 millitary actions to be built into sporters. Anyone here know the ins and outs of case hardening these actions? Such as what mix of charcoal, what temperature, etc?

Perhaps my best bet is to do the action prep and send them off to Salt Lake City and have done. (can't remember the name of the firm that does this work)

[Bret4207]

First off- WHY? Are you talking case hardening or case coloring? Two different things.

[Cactus Farmer]

Bret, Please explain the difference. I case color my single shot actions and they are sure hard. I can case harden without the color but I like the look if it's a visible part.

[waksupi]

Rob, if you are going for color case hardening, the company may not be willing to do it. I know some refuse to do bolt actions, as the heat process can warp the receiver. Turnbull won't.

[robroy]

Color is incidental. The mauser action's strength is because of the case hardening over the low carbon steel.

After bolt lapping, truing the face of the reciever, dressing the threads, and truing the bolt face much if not all of the case hardening is gone.

Warpped receivers are a risk one takes.

[KCSO]

If you send a note to Brownell's they will send you the instructions for their case hardening kits. I don't happen to have a copy here but first you will need an oven and a thermometer. The case mixes are available from Brownell's and you will need a brine tank and dump system. For a Mauser action you will need an insert for the bolt area and for the magazine to help prevent warping. Just like the Old M94 the Mauser is very subject to warping and if I remember right on M94's Winchester charged double for the job to pay for all the warped receivers. My heat treating oven ran $600 bucks and I got off cheap. Figure another say $200 for chemicals and inserts and you are getting into a mighty spendy receiver. But I have seen color cased mausers and they are pretty.

Now please don't confuse the colors on the italian guns with case hardening. They are just chemical colors and do not lend a bit of hard to the gun.

[Ricochet]

Like robroy said, Mauser actions are already case hardened. They're made out of a medium carbon steel in the 1030 class, and case hardened. They're never going to be as strong as an action made out of the high strength steels like 4140, and the controlled feed action leaves some of the case just in front of the head exposed so it's not a good idea to push pressures in Mausers, but that case hardened soft steel bursts in a forgiving, elastic way without making lots of shrapnel.

[Bret4207]

Bret, Please explain the difference. I case color my single shot actions and they are sure hard. I can case harden without the color but I like the look if it's a visible part.

You just answered your own question. I just wasn't sure if he was talking colors or actual hardening. In truth I don;t know just how much difference it'll make as I've seen rock hard, brittle Mausers and still own a butter soft '09 Argie that has no apparent case hardening whatsoever.

[robroy]

I got to looking around and found some info in my notes. Turns out I was asking the wrong question anyway. I'll end up sending the Mausers to Salt Lke City to have the job done once I get the actions worked and ready for barrels. At $75. for the first action and $20 per piece after in the same order I think I gotta do it rather than pay brownells for their case hardening set up

[deltaenterprizes]

I got to looking around and found some info in my notes. Turns out I was asking the wrong question anyway. I'll end up sending the Mausers to Salt Lke City to have the job done once I get the actions worked and ready for barrels. At $75. for the first action and $20 per piece after in the same order I think I gotta do it rather than pay brownells for their case hardening set up

The heat treating will undo all of your truing, true it after it is heat treated.

[Bret4207]

That;'s what I was thinking, but didn;t want to mention. Just how much strength in the Mauser is dependent on HTing? I personally wouldn't bother. Perhaps someone has some definitive knowlege on HTing in Mausers, but this is the first I've heard mentioning case hardening as regards a Muaser. Springfiels and Krags, yes. Mauser- no. Where's the info coming from?

[largom]

Have built dozens of sporters on 98 Mauser receivers and never rehardened any. But then again I have always used FN or VZ24 receivers. Lapping and truing the receivers USUALLY does not remove enough material to effect hardness. Many of the wartime K98's were made of inferior material due to metat shortage and were suitable only for lower pressure use.

Larry

[StarMetal]

That;'s what I was thinking, but didn;t want to mention. Just how much strength in the Mauser is dependent on HTing? I personally wouldn't bother. Perhaps someone has some definitive knowlege on HTing in Mausers, but this is the first I've heard mentioning case hardening as regards a Muaser. Springfiels and Krags, yes. Mauser- no. Where's the info coming from?


Bret,

I believe what is meant by that case hardening statement is that whatever method Mauser heat treated their actions by they have a softer inner core then the outside. Just like heat treating our cast bullets Bret, they aren't as hard in the centers as the outer edges and they sure aren't case hardened. :drinks:

Joe

[StarMetal]

This Mauser action for use with more modern cartridge thing has been going on for years. Kinda of like the debates between which is better the 45 acp or the 9mm.

I've done some research on it in the past and talked to some big name manufacturers about it. One was German. One member who is now in exile said that Paul Mauser built in an additional amount of strength and safety in his Mauser action. That simply is not true. He had no idea of where cartridge performance and pressures would go.
Are Mauser actions tough enough to built modern cartridge rifles on? Hmmmmm...kinda. The safety thing about the Mauser actions are they aren't brittle. They have that softer inner core. If things get to hot for the Mauser the least dangerous thing they do is set the lugs back in the receiver. They usually don't have that catastrophic shattering blow up of the wrong heat treated Springfields.

Newer Mauser actions have better metals and heat treating and we seen many of these in modern calibers. The older Mauser were never meant to be barrels up to the newer higher pressure cartridges. You more then likely will get away building on a Mauser with no problems. This is what has led many to believe they are ideal to build on. Jim Carmichaels once said he would never put a modern cartridge on a Mauser action unless it was re-heat treated.

The only real way to find out is to take a wide selection of Mauser action and sent them to a lab for testing. Testing for metal composition and then for strength.

I found this in my one of my books after posting so I'm editing it in: A word of explanation may be in order: most of the obsolete Mausers were made for 7x57 or 7.92x57. These are or were loaded to medium pressures originally; then it was found that the 8mm had an extremely fast pressure drop. Heavy bullet and heavy loadings could be fired without requiring ultrastrong actions. So a receiver capable of faultless service with the 8mm ammunition loaded to impressive ballistics can set back-fail to hold headspace as bolt lugs are forced back into the receiver metal
when rebarreled to .270, .220 Swift, .30-06, etc.. With the 8mm the pressure goes down the barrel fast; with others, its slows down enough to drive the bolt back into the receiver a little harder. And the more taper to the case, the more bolt thrust against the receiver's locking-lug recess.

Joe

[Bret4207]

Well, if we're talking heat treating that's different than case hardening. One is done to achieve a touch exterior and leave a soft center, the other affects the whole of the item. As I said, this is the first I've heard of case hardening on a Mauser.