308 Small Ring Mauser Conversion?

[Roscoe54]

Some years back I was fortunate to acquire three Swedish M96 Husqvarna actions. Although pre-threaded short chambered Shilen replacement barrels are only available in 6.5mmx55, 250 Savage and 7x57 cals, the Husqvarna company produced a commercial small-ring Mauser rifle in .308 Winchester. I've also found references in a couple of older gunsmithing manuals regarding re-barrelling the military action to 308. Typical chamber pressures of the 6.5mm X 55 are 44,500 CUP (maximum 55,000 psi) while .308 Win is 57,500 psi.

The Swedish 6.5mm x 55 has been my favorite cartridge for years for both hunting and target shooting. I rebuilt one with a 26" Shilen barrel, target stock, Timney Featherweight trigger and other OEM modifications; the first time out, after firing 20 rounds to help break in the barrel, I shot three one hole groups at 100 yards. Except for a few collectibles all of my shooters are close to sub-MOA accuracy. I'm considering the .308 conversion because I want the option of a heavier bullet and extended range. If the accuracy is as good as my 6.5mm rebuild I'll have a very fine long-range target/sniper quality rifle.

I suspect that barrel makers don't offer pre-threaded SRM bbls in .308 Win because it would NOT be safe to use them with inferior SRM actions (such as Spanish) that lack the strength and tolerances of the M96 Swede. I've tested my receivers for Rockwell hardness and all are finely-finished between-war production.

Sorry for the long-winded intro, but I believe that the Swede is safe at the chamber pressures of a 308 Win. Does anyone out there have any experience of reasons why I should have reservations about chambering this small-ring action for .308? Thanks for any info.

 

[valnar]

Other than having the action handy, is there a particular reason why you want to use a small ring Mauser for a .308 over a large ring....or something more modern like a Remington 700?

I can see rolling your own 6.5x55, but a perfectly fine modern off-the-shelf .308 rifle would probably be better.

 

[Ronin8451]

I have an old Argentine arsenal rebarreled mauser in .308 and I have only shot the 7.62x51 lower powered surplus thru it after trying a Federal .308 hunting round and it jammed the bolt. It might hold up, but I like the big ring mausers for the .308, much safer.

 

[browningguy]

The '96 may have been the best action of it's era, and my personal feeling is that most of them will take .308 pressures with no problem. And i know of at least 2 that have been shooting .308 since the 60's with no problem.

But ... metallurgy and inspection were not simply not as good at the time as they are now so why take a chance? I'd stick with pressures it was originally built for personally.

 

[Don357]

Weren't the Spanish Civil Guardia Mausers and FR-7 and FR-8's barreled in .308Win or were they 7.62X51 NATO?. I'm almost certain that the Spanish CG's were small ring, but not sure about the FR's.

 

[TurtlePhish]

I think the FRs were 7.62 CETME. Much lower pressure than either .308 or NATO.

 

[Roscoe54]

The Spanish FR8 CETME carbines are large ring Mauser 7.62 NATO (I owned one, a cool carbine with a rotating aperture receiver sight and an HK-style front). I heard they were used as training rifles for the automatic CETME. In any case, the barrels were stamped 7.62x 51, not CETME, and I fed 60 rounds or so of .308 Winchester through mine with no pressure problems.

If I had an LR Mauser action I'd use it for the .308, but unfortunately I sold off most of my collection when I got in a financial bind and SRM actions are all I've got left. I guess the bottom line is that I like to build custom rifles because I can; I enjoy owning one-of-a-kind tack-drivers.

BUT it's idiotic to spend good money on an expensive conversion, and a good point about simply buying a new rifle--My local Cabela's has a used Remington 700 SRS Tactical in new condition for $500; only problem is my bank account is about $450 short. I've also looked at the Weatherby Vanguard in .308, new for around $450. It's a plain-vanilla rifle with few OEM accuracy parts available, but I've read a couple of reviews claiming sub-MOA accuracy out of the box.

I've had my antenna up for a good deal on a Rem 700 or (in my dreams) a pre-64 Winchester Model 70 for some time...by the time I got done with machining costs I'd have a large chunk of change sunk into a Mauser .308 conversion. Many smart shooters have finally caught onto 6.5mm x 55 in recent years (I've been a cheerleader for 25 years) and my custom Swedes have sold easily in the past. I'm an ex-FFL gunsmith--I dropped my license because the paper requirements and a surprise ATF home visit made it more of a hassle than it was worth. I had a pretty narrow niche in restoring military rifles to better-than-new shooting condition, plus doing custom stock work, metal polishing and re-bluing. I'm not a full-service gunsmith and have limited machine tooling, but lotsa people like their guns to be pretty and for a few years it was a profitable sideline home business.

That said, I think I'll use my remaining Husqvarna actions for 6.5 x 55 custom guns...I even have a few in-the-white 24" carbine factory barrels on hand. I replace the bolt handle with a TIG-welded custom teardrop handle, install a 1-piece Redfield scope mount, modify the cocking piece, eliminate the bolt safety, install an OEM bolt shroud and Timney trigger w/safety, re-shape the trigger housing, replace the barrel if needed and make a few other tweaks before steel-bedding the action in a walnut stock (I leave the butt uncompleted so I can customize the drop and LOP to customer preference). I used to polish 'em to mirror finish and have them hot-blued, but the EPA has shut down my bluers so I now use Dicropan IM hot water blue or DuraKote in my garage, or can have a local guy Parkerize 'em. The end result is a light quick-handling rifle, a target trigger w/instant lock time, a stock married to your body and the near-unrivalled accuracy of the 6.5mm Swedish cartridge.

It'd be dumb to stray from something I know and venture into new territory, so I should have a pair of Swedes for sale in a couple of months.

SO, a Remington 700 .308 it will likely be--it's the most versatile rifle out there, I've worked on 'em for customers and it was the chosen military sniper rifle back in my service days, with more than a few quarter-mile kills (I've read recently that the Win. M70 was standard sniper issue but I don't recall seeing any among USMC and LURP detachments I crossed paths with).

Yeah, I know that these days there are flatter-shooting heavy rounds out there but I'm a traditional old fart.

Does anyone have anything to say about the Weatherby Vanguard? I've handled a couple and have been reading about it but I've never fired one...my impression is that the only thing cheap about it besides price is the stock: The action is very smooth, the design is dirt-simple, the factory trigger is nice and I'm thinking that a pillar-bedded bbl in a custom stock might have possibilities.

 

[Slamfire]

Loading manual data must be conservative due to the fact that the 6.5 Swede round may be fired in receivers going all the way back to 1896.

Swedish service round pressure had to be conservative due to the fact that they had rifles with receivers going all the way back to 1896.

People today do not appreciate the primitive state of metallurgy that existed prior to the 1920’s.

 

[lonniemike]

And all this time I had thought that the reason Sweden and Denmark kept the pressures in the mid 40's was because of the primative metallurgy of the single locking lug on the 6.5 Karg-Jorg just like the US Karg.Best

 

[Slamfire]

single locking lug on the 6.5 Karg-Jorg just like the US Karg

There are differences in the Norwegian Krag. Frank De Hass thought them stronger because the guide rib and the lug made contact to the receiver and that the Norwegian Krags were made of better steels.