Mauser 93 to 7.62x39

Son of Sam · Nov 6, 2015

I was given this action and even posted a thread a while back about intended uses. Since then its been sitting in the corner of my office collecting dust. A few days back I decided I want to move forward so I ordered a 21" short chambered 7.62x39 barrel from GunParts and a mag kit from eBay.
Does anyone sell an extended extractor? The action was robbed of an extractor when it was given to me. So, either way I have to buy an extractor. Still have all my machine work to do, trueing, lapping, head spacing. From those of you that have done similar projects. Is there any particular issues that I may run into with this build? I have several more builds planned after this. But I figured this is relatively simple place to start.

abarnsley · Nov 6, 2015

You were given a cheap action..

Missing extractor.

Want to blue print and lap in a bolt, so you can end up with a rifle that will shoot 1.5 in groups.

Bought a cheap no name barrel. Probably .308 bore.. Going to have custom sizing dies made $$$, so you can reload??? Be a shame to lap and true an action, to run steel case ammo through.

Are you so cheap, that building a really nice rifle is impossible?

You say you have a big shop, but never seem to want to start a project that will cost over 150.00

Perhaps the homeshop boards, would be a better place to hang out..

Issues.. yes.. many mag kits as you call them, barely work, piss poor stamping, generally poorly made. Reliable feeding can be an issue.. And a dirt simple bolt gun, should NOT have feeding issues..

Plenty of books out there on gunsmithing.. Nothing in a 93 Mauser is state of the art.. Including gas handling in the event of case failure..

Son of Sam · Nov 6, 2015

Wow. Who pissed in your cheerios.
Not to mention you dont judge a chef by how well he cooks a fillet, you judge him on how well he cooks the worst cuts.
Mag kit- is a wolf spring, follower and a spacer block. Not a removable mag.
I havent slugged the barrel yet. But, if its .310 or .308 dies are the same price and often in the same pack. I dont expect a precision rifle, hunter 1-1/2 MOA or better is fine. However everyone who has posted about this combo has claimed MOA or better.

ditchdigger · Nov 6, 2015

If I ever build a rifle that'll do no better than 1 1/2" I'll know it's time to quit or just go to WalMart and buy some off the shelf POS. Short chambered barrels, I won't use 'um,,, not even if the customer supplies it. Mauser '93,,, not a chance, I've got better things to do with my time. Not to piss in your Cherrios, or anything,,,,,,but time is precious, use it wisely..... Sounds like a 'home shop' job to me, not that there's anything wrong with a home shop. It's a project for someone who doesn't have anything better to do......

GGaskill · Nov 6, 2015

On what I hope is a more helpful note, those Mauser actions were mostly case or pack hardened so you can't lap much without losing that strength. I would limit modifications to the bolt and receiver to things like drilling and tapping for scope mounts, even for low powered cartridges like 7.62x39.

paracongo308 · Nov 6, 2015

You can make your rifle Fire when you get it safely head spaced, however you will be picking the empty cass out of the receiver. Your Mauser bolt face is made for a .473 case head, the 7.62x39 has a .445 head diameter. You have to know this shit before investing money in any project.

gzig5 · Nov 6, 2015

paracongo308 said:
You can make your rifle Fire when you get it safely head spaced, however you will be picking the empty cass out of the receiver. Your Mauser bolt face is made for a .473 case head, the 7.62x39 has a .445 head diameter. You have to know this shit before investing money in any project.

That might be why he was asking for an extended extractor. Least that is the way I took it. What is with all the negativity today?

paracongo308 · Nov 6, 2015

gzig5 said:
That might be why he was asking for an extended extractor. Least that is the way I took it. What is with all the negativity today?[/QUOTE

What good is a extended extractor when the slot in the bolt face is machined for a different size case. You have to Tig weld the face of the bolt just in the guide area and remachine the bolt face slot to .445.-.447 and while he is at it Tig the tip of the extractor and rework it.

Son of Sam · Nov 6, 2015

Now I have learned something. I was under the impression that the smaller cartridge would work fine with the slightly larger bolt head because the chamber would hold it into place. It does make sense to get full ejection.

paracongo308 · Nov 6, 2015

Son of Sam said:
Now I have learned something. I was under the impression that the smaller cartridge would work fine with the slightly larger bolt head because the chamber would hold it into place. It does make sense to get full ejection.

You can visualize it better if you hold a AK round against your bolt face. You will see how much play is there. What your attempting to do is ok, just more work involved.

ditchdigger · Nov 7, 2015

Tig the bolt face and then machine it to the proper size and then pay a heat treating firm to have it re-heat treated. The negativity? Well, maybe it's the rush for all "to do their own work!". You'd think by reading the forums these days that the only reason a person becomes a gunsmith/machinist is because they're too stupid to learn to do anything else. That goes hand in hand with paracongo308s' post, "You have to know this shit before you invest money in any project".

CalG · Nov 7, 2015

And how does one "Know this shit"?

ditchdigger said:
Tig the bolt face and then machine it to the proper size and then pay a heat treating firm to have it re-heat treated. The negativity? Well, maybe it's the rush for all "to do their own work!". You'd think by reading the forums these days that the only reason a person becomes a gunsmith/machinist is because they're too stupid to learn to do anything else. That goes hand in hand with paracongo308s' post, "You have to know this shit before you invest money in any project".

What better way than to ask and DO?

There is not logic in every task attempted.

ditchdigger · Nov 7, 2015

And how does one know his shit! By getting some PROPER instruction! Proper instruction does NOT include going to the internet! The simple bolt face difference could be found in any reloading manual. Simple observation of how the action works should tell any simpleton that it might fire, but extraction and ejection are pretty much out of the question. There are schools out there,,,, some two years long and some week long seminars. Sounds like a good place to start, to me. The on-line 'schools' an the gunsmithing forums form the basis of the mis-information super hi-way. Most of this internet crap is just that,, Crap! There's a reason I don't visit this forum often. It serves no purpose other than to piss me off....... Post Script; There SHOULD be logic in every task attempted! Otherwise, you're just runnin' blind.

CalG · Nov 7, 2015

Ditch

Thanks for the crap!
It's rewarding to see what comes out with a bit of goading....

I've learned a lot ;-)

Formal education is costly. A Simple heads up?...priceless.

72bwhite · Nov 7, 2015

The bolt face size is exactly why I haven't chambered my turk mauser in 223.
much easier to open it up then shrink it.
and just too lazy to make one from scratch out of 4041 PH
and well is it really worth the effort

john.k · Nov 8, 2015

The usual milsurp action for 7.62x39 is the Carcano.I see lots of these in hire fleets at rifle ranges.A SMLE barrel is cut off at the threads,and the remaining part .303 chamber is exactly right for the Russky case.Rethread the knoxform to 1.040"x14tpi.This is damn close to 3/4 waterpipe thread,and I have heard of the thread dies being used.The mag setup works,as the case has a similar base size, and so the extractor doesnt need alteration either.The whole gun can be finished in less time than altering the Mauser bolt,and for little cost.The Type 38 Jap rifle also has a similar size small case head and is a lot easier to do than a 93.----Al Cheapo,the peasants gunsmith.

deltaenterprizes · Nov 8, 2015

I bought one of these conversions from a friend of a friend that was not completed.
Since the case head size difference is small, to get reliable extraction instead of welding on the extractor, I used a grinder to remove metal from the protrusion on the inside of the extractor and regent it to allow it to go in further and grab the case head.
The bolt face was not modified.
I used dummy rounds made from Berdan primed steel cases found on the range to check feeding and extraction/ejection.
Most 7.62x39 die sets include expanders for .311" & .308" diameter bullets.

Son of Sam · Nov 9, 2015

paracongo308 said:
Your Mauser bolt face is made for a .473 case head, the 7.62x39 has a .445 head diameter.

This was never in question. The question is if the extractor and bolt face work reliably with .014 gap around the case head. According to "deltaenterprises" at least one bolt left at .473 does work. If it doesnt work or shouldnt work then I will go another route. The idea of making a new bolt sounds interesting and would also cure some of the other issues with the sloppy action.

I post to the board as a machinist asking questions about gunsmithing projects so that I dont make mistakes that are obvious to those who have done them in the past. Its a hobby that plays off of some of my career skills. I dont have time to go take gunsmithing classes because I have a business to run as well as a family to raise. Having the machining and metalworking resources this project as well as any others is IMO able to be accomplished with a little guidance. I know enough (hopefully) to be able to weed out the bad advice.
If you feel threatened by a novice asking questions then please dont reply. To the others. I really appreciate the information and guidance you share. IMO its critical for the industry to survive.

Son of Sam · Nov 9, 2015

72bwhite said:
The bolt face size is exactly why I haven't chambered my turk mauser in 223.
much easier to open it up then shrink it.
and just too lazy to make one from scratch out of 4041 PH
and well is it really worth the effort

It probably isnt worth the effort. But, dont let that stop you. Turk Mauser certainly isnt a highly regarded rifle it is none the less an important part of history. Its nice to give it a new use.

akajun · Nov 9, 2015

I have a Mexican Mauser that century had converted to 762 39. As I received it the handle was bent and the action drilled and tapped, sporter stock and unknown sporter barrel. It shot ok with American brass case ammo , till I bedded it and put a Timney trigger on it, at which time it became a sub moa rifle , with good American ammo or my hand loads . With steel cased anything it opened up to 4-5". I keep the steel case ammo for my aks. I seriously doubt that century trued the bolt or action in any way , and due to the fact that mausers are thinly case hardened, only square up the receiver face, leave the lug abutments alone.
Anyway I let a friend borrow it for his wife, who loaded a round directly into the chamber not from the magazine, which broke the extractor . I bought a blank extractor from brownells and fit it. However I also took a standard 8mm extractor and welded it up with my mig, then ground it down , it also worked till the blank one came in.
So it can be done, but don't think you are gonna take wolf / Tula steel case and drill one hole.

Mauser 93 to 7.62x39

Aluminum

Titanium

Aluminum

Aluminum

Titanium

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Hot Rolled

Banned

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Banned

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Diamond

Aluminum

Diamond

Titanium

Diamond

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Aluminum

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