Old Mauser New Barrel 6.5mm-06 or 6.5x57mm

sigshepardo

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I have a 1943 Mauser Kar98k that I plan on re-barreling. I want an extremely accurate, sub-moa shooter. The new cartridge cannot exceed 3.30 C.O.L due to the old magazine. What do you guys think would be best for me? I shoot target, not game. I was thinking about the 6.5mm-06 or the 6.5x57mm. But I am open to all other ideas. Also if I could get somebody who knew about how accurate the above mentioned cartridges are would be great. Thanks.
 
I'm not sure what your options are as far as ammo for either one goes.
I have a 6.5x55 swedish and I just looked at Cabela's to try and help answer your question. The only caliber they carry online that comes close to what you are talking about is 6.5x52.
Not sure this helps much, sorry.
 
Your action was tuned for 8mm mauser, and may not feed and extract the cartridges you mentioned reliably, but would work very well with 7mm mauser.
 
I have a 6.5X06 in a Mod 70 Pre 64 target action. I also have a 260 Rem on Mod 70 and 7/08 on Win Action.

I believe the 6.5X06 round is way too long for 8MM action. I would do the 260 Remington in the 98 action or the 7MM/08.

I would also order a 5A contour barrel which will allow you to cut off threads and rechamber the barrel at least twice. Start with a 26" barrel.

I would strongly consider buying a 260 Rem reamer from Dave Manson with custom dimensions to give you longer brass life.

PM me if you have any specific questions I can help with.
 
As Hummer suggests, the 260 Remington might be an option for you, but you might have to adjust the feed rails if you go with it as the case has less taper than the Mauser's feed rails were designed for. I've had that issue in the past when barreling an old 98 to 7.62 NATO. Have you thought about the 257 Roberts? It's based on the Mauser cartridge and there's a good choice of bullets available for it. I'm conteplating building a Pre-64 Winchester up in that calibre as a light rifle for my son.

Another option might be the 6.5 Swede. It has a head diameter slightly larger than the Mauser-30/06-7.62 NATO series of cartridges at .480 v. 473. I don't know if that would mean adjusting your extractor and feed rails or not. It is well liked by those that have 'em, but I've never owned a Swede so that's the best I can offer you regarding that particular Scandanavian.
 
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I have owned both, and I think you would enoy the 6.5X57 more. It would be a very nice shooter (in addition to being somewhat unusual). As an upside, you would not have to rework either the feed rails nor the magazine box since the cartridge is based on the 57mm case.

Don't get me wrong, the 6.5-06 is a great cartridge, and will perform in the long-range department just fine (at least as well as the 6.5-284 does, since it will launch the same proectile at the same or higher velocities as that cartridge). You will find that the 6.5X57 will come within about 200 fps of the 6.5-06 velocity, but without the muzzle blast and added recoil due to 10% less powder being burnt.
 
If its a nice and original gun I can see any point in butchering it, those old Mausers can fetch a decent amount of money, they're not a dime a dozen like a Mosin Nagant.

For calibres, if you like to burn barrels out quick then go for a 6.5-06.
But a 260 rem will do basically the same thing but with less barrel wear, and cheaper reloading components.

Unless you are willing to spend a lot of money on your rifle I can't see much point in getting much more than a 308 or even a 7mm-08.
I think you'll probably be better off to sell the Mauser and buy a nice heavy barrel Savage in 308, and if you must rebarrel it to 260rem.
 
IIRC,A Warren Page designed wildcat is the 260 AAR,for "All Around Rifle"It is a257 Roberts Ackley Improved ,but a 6.5 instead of a .257.
I have seen reamers and dies listed in Midway,I believe,as "6.5x257 Ackley Improved",it is standard enough you won't have to spend a fortune.

You can neck down 7x57 easily to fireform.

For my time and effort,I absolutely agree the .308 family of cartridges ,including the .260,will likely have feed problems in a Mauser.To me,it just makes more sense to use the family of brass the rifle was designed around.

I would not look so much to the cartridge for accuracy.

A little blueprinting on the action,like lapping the lugs(don't just pull back on the bolt handle,there is a proper tool)

A squaring cut on the face of the receiver ring..

Fitting the bbl threads,and how the bbl seats to the receiver..A sharp reamer cutting a nice throat..

A good barrel

Bedded,strain free and free floated in a stiff,stable stock.

Good trigger,quality optics

brass prep,developing the right load,straight,concentric ammo and shooting well,all those things will matter more to accuracy than the cartridge name.

Good luck,sounds like you have a good plan,pretty much,except I also agree that if your Mauser is a complete,original rifle ....I'd discourage altering it.

Do as you wish with what is yours,but you will not save any money altering a milsurp.
 
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First I've heard about a 6.5-06 burning barrels. This is not my experience. Lots of brass, lots of bullets to use.
 
My 43 M98 has been rebarreled to 6.5x55 .Nothing wrong with the accuracy of that cartridge.No other changes necessary.
 
Hodaka,
If you get a chance to have a looksee with a good borescope you will see throat erosion and fissures well initiated at 300 rounds. I have 475 on mine now. I am running 53 gr. Reloader 22 with 142 Gr. Matchkings in a min dimension chamber 6.5X06 cut with a Manson reamer to my dimensions which are .468 on the base and .293 on the neck. This requires case necks to be turned to .292 or .291 and it shoots quite well.

The above load in a 30.5" barrel comes out and 3015 on the chronograph and my best SD is with Wolf primers using LC63 Match brass turned on the neck.

I order my barrels with full dimension about three to five inches in front of action so I can cut off threads and set barrel back as needed.

Most match shooters using 6.5s say they are gone at 800 rds for long range match use. This thing is a extremely flat shooter. I also have a 260 I get 2675 fps on a 28" barrel that does well.

Sherri Gallagher holds the National Championship Record with a 260 of 2396 out of 2400 possible score from 200 to 600 yards.
 
Hummer, it sounds like you have experience. I no longer have my 6.5-06 but now have a .260 and a Swede. I like them all. I know that a 6-06 has a barrel burning reputation but your info is the first I've heard about the 6.5. Thanks.

ps - I used a lot of IMR and AA 4350 and H-4831.
 
The new cartridge cannot exceed 3.30 C.O.L

This right here says go with the 6.5X57.

The -06 can make that OAL, but you lose the ability to seat the bullet farther out as the barrel wears. And with the long heavy 6.5mm match bullets, you have a lot of room for seating long.
 
I've had good results from a couple of 98 Mausers rebarrelled to 25/06. Very accurate, great on deer &coyote, and factory ammo is readily available.
 
I'd go 6.5x57 utilizing the original brass for that action & shouldn't have any feeding problems. 6.5 bullets have an awesome ballistic coefficient and should have plenty of horsepower out of that case. my .02 cents
 
I have a Carl Gustaf Swedish mauser 6.5-55 and its a bad ass round. Very flat shooting. Didnt have to do a thing but shoot it. Got a $ 100 bucks in it. Heres a picture of the 6.5-55 beside a 30-06. 6.5 is on the right.
IMG148.jpg
 
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Ive got a Mauser Rebarreled to .308 and have feed problems with the shorter cases. If I were to rebarrel one on purpose, I would try to have something in the same family as the 8MM Mauser Mauser.
 
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