Converting a Mauser to a 7.62x39

It would likely be cheaper to just buy a Ruger bolt gun to shoot your ammo in.

I've seen chamber inserts for converting a .308/7.62x51 Mauser to 7.62x39, but if yours is a 7mm or 8mm Mauser, it will need a new barrel. That's not going to be inexpensive.

I have an Arisaka converted to 7.62x39 by the Chinese. They used an SKS barrel. Took the original 6.5mm barrel, cut it off and threaded the stub to for the SKS profile. No modification to the bolt - it feeds, extracts, and ejects pretty reliably.

I would think you could also cut back a Mosin Nagant barrel and rechamber it.

Conversion...

Ruddie--I agree w/the above posters who say that the conversion would cost more than it's worth. And more than just buying a 7.62x39 rifle new, in which to burn up yr ammo. BTW, CZ makes a nice little rifle in 7.62x39, all set to go.

On another topic, could you please explain what you meant by

I have a GEW 98 that is a little rough around the edges.

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If it needs a stock, that can be done. If the stock just needs refinishing, that can be done. If the rifle is battered enough to be mechanically unsound, it hadn't ought to be shot at all, IMNSHO, in 8mm OR in 7.62x39.

i've seen a few sr mausers converted & numrich even sells the barrel & feed kit for them.
as far as cost goes if you have the ability to do the work yourself it is not very expensive or difficult.
most of the 7.62x39 bolt rifles on the market use a .308 barrels instead of the .312 barrels.
just have pacific grind the reamer with a slightly longer lead for a .308 barrel.

parts would run $100-150 for the barrel, $200 for the reamer & gauges, & $30 for a blank extractor. you could rent the reamer & gauges to save some money but i prefer to buy them for use on future projects.

if you have a decent smith the job should only be slightly more expensive than a standard rebarrel job. having to fit the extractor blank and soldering a bushing to the boltface to reduce it down for the x39 casehead would be the main differences in the conversion from a standard rebarrel.
sr mausers have been made to feed with a magazine spacer and i'm sure with some tweaking a lr mauser could do the same. on .223 mauser conversion a ruger mini-14 mag is cutdown & solderedd to the floorplate and i think the same thing might work on a x39 conversion.

The .472" breech face of the Mauser will be too large for the 7.62x39 and you'll likely have extraction issues unless you have the bolt/extractor modified. The barrel will need to be replaced, and the magazine well will need to be modified to reduce the box size. Even after that, there is no guarantee that the gun will feed reliably and you may wind up having to rework the receiver rails to adjust to the smaller case diameter of the 7.62x39 round.

It really will be cheaper to just buy a Ruger or CZ.

If it's a nice Gewehr 98, I wouldn't butcher it. I think a Mini-14 in 7.62x39 was always an attractive option.

Concur on all points- why butcher a Gew, buy something else and have two guns, and it's a huge pain in the ass. A rifle designed and built for X is not really the best thing to change into Y after the fact, not even if somebody makes a kit or you're handy with tools, it's just more effort than it's worth.

A rifle designed and built for X is not really the best thing to change into Y after the fact, not even if somebody makes a kit or you're handy with tools, it's just more effort than it's worth

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if that was the case there would be no custom rifles and everyone would be shooting generic store bought crap. it may not be worth the effort to some but some of us actually like building our own rifles. i don't see a 7.62x39 conversion as even a slightly difficult project
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i think the attitude against building your own guns shows just how little skill is left in the general population.
i get real tired of hearing it'll cost as much as a new remchester or it will never feed from people who have never built anything.

It is a total disservice to say that the cost of a conversion such as this is as cheap as a new rifle OR that anyone can do it at home. A bbl vise and action wrench is not mentioned (oh yeah, I forgot about the standard pipe wrench.....) I have been in the biz over 20 yrs and never met a smith that would tell you a conversion such as this is cost effective. I get to do a lot of repair that "kitchen table" gunsmiths have worked on. They pay my salary on a regular basis. What about bluing the bbl? Drilling and tapping? Bolt forging or welding? Mag box work or changing the safety (for a scope). Feed rail and bolt face work for the novice???????? I don't think so...There is a reason I don't work on choo choo trains or the Space Shuttle

Zastava makes a mini mauser, as does CZ
the Zastava was imported by Charles Daley, I think either Remington or Winchester imports them now, they are based on the K98/M48 action.

the problem with 85% of the smiths today is they are assemblers instead of actual gunsmiths.
they lack the skill & creativity to overcome small problems like reducing the boltface down for the smaller casehead, modifying the extractor and solving feeding issues so they price the work where no one would have them do it.

i've seen just as many botched jobs come from smiths as i have seen come from bubba & billy bobs kitchen table.

i have a mini-mauser in 7.62x39 but a fullsize 98 would still be neat.
i think if i was to do one i would do it on a shortened turk k kale then surface grind the receiver down to resemble a g33/40. i just happen to have a k-kale action in the corner and i need another project like i need a hole in my head.

Zastava makes a mini mauser, as does CZ
the Zastava was imported by Charles Daley, I think either Remington or Winchester imports them now, they are based on the K98/M48 action.

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Mini Mauser is not true mauser action. It is push feed. Most recent importer is Remington (Rem 799). I have one and the extractor chipped only after no more than 60 rounds. I want to think it is a factory defect and not the norm, but they would not repair it under warranty. By the time I noticed it, I was 15 days passed the 1 yr warranty. Now EAA is the service center for these rifles.

Edit: received my new extractor. The original one that chipped appears to be a defect. The new one is definitely more robust.

Anyone that gets an honest quote from a reliable qualified smith will tell you that the cost of a conversion such as this is considerably higher than buying the rifle new. A few phone calls is all it takes; while you're talking to the man, get a list of the tooling it takes to do the work, then price those. If he's truthful he will also tell you that the conversion should NEVER be undertaken by someone without the proper training (which was the subject of the op in the first place). I would think just about anything can be done if you throw enough money at it but in this instance you will fastly approach a point of diminishing returns. Most folks that want this type of work will never do it to save money; it's done because they have their perfect rifle in mind and cannot find it on the shelf. Most guns today are more accurate than the average shooter and are available for a greatly reduced price compared to a conversion.

As posted above, the bolt face is too big for that cartridge. Also, you will not get reliable feeding of such a short cartridge in a long action and large magazine box. Extraction would be non-existant because of the large bolt face. Just buy a handi rifle for under 200 bucks and go have fun......chris3

asking the smith what his equipment cost is irrelevant, he must have the equipment to do a standard barrel job. the only thing he might not have on hand is the reamer & h.s. gauges if they are not a common caliber.

it seems as though a bunch of keyboard pounders with no smithing experience have thrown down the gauntlet on this conversion and i accept the challenge and my 7.62x39 mini mauser will have a bigger brother.

after about 30 minutes of playing around with some 7.62x39 ammo and couple of my parts guns i can already see this is going to be easier than i thought.
the extractor works as is & will work even better when i solder the bushing to the bolt face to reduce it down for x39 case head.
ejector needs about .025 added to it to work reliably, it will eject as is but not as good as i would like.
feeding will need a little work. left side feeds good, right side doesn't. a new follower might fix it but i'll probably just attach a shortened mini 30 magazine to the top of the floorplate and be done with it.
reamer is about two weeks out and the barrel will be ordered on friday.
total parts should come in about $400, i'm including the price of the reamer & gauges even though they should not be included in the price of a build because they are used on other projects as well.

The 7.62x39 has a rim diameter of 11.35mm, and the 8x57 has a rim diameter of 11.95mm. My converted Arisaka uses a 6.5 Jap bolt, which is designed for a 11.85mm rim, and extracts 7.62x39 very well. It will occasionally drop the round before ejecting, but it never fails to extract it. I would think that the additional .1mm difference from using an 8x57 bolt would not change things significantly.

Here's how the Chinese dealt with the magazine length:





Those two tabs block the tips of the rounds in the mag and prevent them from moving forward. The top round is free to move, though.

I've seen another Arisaka conversion that used a shortened follower and a block in the back of the mag - effectively shortening the whole magazine to fit 7.62x39.

Phaethon:
My nice wood/stainless Mini 30 (Mini 14 in 7.62x39) needs no work.

ruddie:

Make a few calls to actual gunsmiths and see what they would charge for this conversion in finished form then you can post your findings here for us all to see. It goes without saying that misinformation runs rampant on a lot of forums. It was implied by one poster that anyone can do the conversion at home which is what I took exception to and still maintain. The listed parts and minimal tooling mentioned already approaches the cost of a new gun and you're just getting started. Obviously a gunsmith will have most if not all of the tooling but if you are not one, you will have to purchase, borrow or pay a smith to do the work you can't yourself. There is a lot of diff between sticking on a bbl and finished product. Even with a pre threaded , crowned and short cham bbl, you still have to drill and tap for a scope or drill and tap for irons plus the cost of the sights, blue the bbl (hopefully with the rest of the gun so it will all match) rework the bolt (unless you use irons) just to name a couple. I have been doing these conversions for 20 years in cals from 22-250 to 458 American on the 98 actions and I don't recall a single FINISHED product that cost less than a new Savage for instance. To say that the average person (not a gunsmith with tools) can do this at home is a appalingly incorrect statement. Trust none of us; research yourself and let us unknowledgeable "keyboard pounders" know...........hehe

I have a 8mm Mauser, converted by the Israeli’s to 308 Win.. Does not feed reliably. I converted a 7mm Chilean Mauser to 308 Win and it feeds reliably.

Flip a coin, might work, might not.

I would not bother with it. Too much cost and you won’t get your money out of it.

Slamfire 1

If you don't have a short follower and mag box spacer you can obtain the kit from Sportsmans Guide. The mag spacer is scwed or epoxied to the rear of your mag box to limit cart shifting. Just cut down the spacer to size needed to allow the cart into the box without excess fore and aft play, replace the spring and follower with the new shorter one and I would think it should not need anything further. Just a thought.....

Hey Gunplumber, nice to see you over here. For those of you that don't know, this is a good reliable smith. He refinished my Savage 99 in Metacol years back and it's been doing just fine since

I'd be taking his word on the amount involved. But, that aside - I do think that early SR Mausers are good candidates for a custom 7.62x39 bolt gun. I just wouldn't look at the project in a dollars and sense way. I'd be more inclined to look at the overall build as a decent project to get a very unique rifle. If it's done right, it should feed and fire just fine